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  • 1.
    Ahrentorp, Fredrik
    et al.
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Blomgren, Jacob
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Jonasson, Christian
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Sarwe, Anna
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Sepehri, Sobhan
    Chalmers University of Technology, Göteborg, Sweden.
    Eriksson, Emil
    Chalmers University of Technology, Göteborg, Sweden.
    Kalaboukhov, Alexei
    Chalmers University of Technology, Göteborg, Sweden.
    Jesorka, Aldo
    Chalmers University of Technology, Göteborg, Sweden.
    Winkler, Dag
    Chalmers University of Technology, Göteborg, Sweden.
    Schneiderman, Justin F.
    University of Gothenburg and MedTech West, Göteborg, Sweden.
    Nilsson, Mats
    Stockholm University, Stockholm, Sweden.
    Albert, Jan
    Karolinska University Hospital, Stockholm, Sweden ; Karolinska Institutet, Stockholm, Sweden.
    de la Torre, Theresa Z. G.
    Uppsala University, Uppsala, Sweden.
    Strømme, Maria
    Uppsala University, Uppsala, Sweden.
    Johansson, Christer
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Sensitive magnetic biodetection using magnetic multi-core nanoparticles and RCA coils2017Ingår i: Journal of Magnetism and Magnetic Materials, ISSN 0304-8853, E-ISSN 1873-4766, Vol. 427, 14-18 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We use functionalized iron oxide magnetic multi-core particles of 100 nm in size (hydrodynamic particle diameter) and AC susceptometry (ACS) methods to measure the binding reactions between the magnetic nanoparticles (MNPs) and bio-analyte products produced from DNA segments using the rolling circle amplification (RCA) method. We use sensitive induction detection techniques in order to measure the ACS response. The DNA is amplified via RCA to generate RCA coils with a specific size that is dependent on the amplification time. After about 75 min of amplification we obtain an average RCA coil diameter of about 1 µm. We determine a theoretical limit of detection (LOD) in the range of 11 attomole (corresponding to an analyte concentration of 55 fM for a sample volume of 200 µL) from the ACS dynamic response after the MNPs have bound to the RCA coils and the measured ACS readout noise. We also discuss further possible improvements of the LOD.

  • 2.
    Alcusa-Sáez, E. P.
    et al.
    Departamento de Física Aplicada y Electromagnetismo-ICMUV, Burjassot, Spain.
    Díez, Antonio
    Departamento de Física Aplicada y Electromagnetismo-ICMUV, Burjassot, Spain.
    Rivera-Pérez, E.
    Departamento de Física Aplicada y Electromagnetismo-ICMUV, Burjassot, Spain.
    Margulis, W.
    RISE - Research Institutes of Sweden, IKT, Acreo. KTH Royal Institute of Technology, Stockholm, Sweden.
    Norin, L.
    RISE - Research Institutes of Sweden, IKT, Acreo. KTH Royal Institute of Technology, Stockholm, Sweden.
    Andrés, M. V.
    Departamento de Física Aplicada y Electromagnetismo-ICMUV, Burjassot, Spain.
    Acousto-optic interaction in polyimide coated optical fibers with flexural waves2017Ingår i: Optics Express, ISSN 1094-4087, E-ISSN 1094-4087, Vol. 25, nr 15, 17167-17173 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Acousto-optic coupling in polyimide-coated single-mode optical fibers using flexural elastic waves is demonstrated. The effect of the polyimide coating on the acousto-optic interaction process is analyzed in detailed. Theoretical and experimental results are in good agreement. Although the elastic attenuation is significant, we show that acousto-optic coupling can be produced with a reasonably good efficiency. To our knowledge, it is the first experimental demonstration of acousto-optic coupling in optical fibers with robust protective coating.

  • 3.
    Arndt, Holger
    et al.
    Spring Techno GmbH & Co, Germany..
    Burkard, Stefan
    Spring Techno GmbH & Co, Germany..
    Talavera, Guillermo
    Universitat Autònoma de Barcelona, Spain.
    Garcia, Joan
    Universitat Autònoma de Barcelona, Spain.
    Castells, David
    Universitat Autònoma de Barcelona, Spain.
    Codina, Marc
    Universitat Autònoma de Barcelona, Spain.
    Hausdorff, Jeffrey
    Mirelman, Anat
    Tel Aviv Sourasky Medical Center, Israel.
    Harte, Richard
    National University of Ireland, Ireland.
    Casey, Monica
    National University of Ireland, Ireland.
    Glynn, Liam
    National University of Ireland, Ireland.
    Di Rosa, Mirko
    Istituto Nazionale Riposo e Cura per Anziani, Italy.
    Rossi, Lorena
    Istituto Nazionale Riposo e Cura per Anziani, Italy.
    Stara, Vera
    Istituto Nazionale Riposo e Cura per Anziani, Italy.
    Rösevall, John
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Rusu, Cristina
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Carenas, Carlos
    EURECAT, Spain.
    Breuil, Fanny
    EURECAT, Spain.
    Reixach, Elisenda
    EURECAT, Spain.
    Carrabina, Jordi
    Universitat Autònoma de Barcelona, Spain.
    Real-time constant monitoring of fall risk index by means of fully-wireless insoles2017Konferensbidrag (Refereegranskat)
    Abstract [en]

    Constant monitoring of gait in real life conditions is considered the best way to assess Fall Risk Index (FRI) since most falls happen out of the ideal conditions in which clinicians are currently analyzing the patient's behavior. This paper presents the WIISEL platform and results obtained through the use of the first full-wireless insole devices that can measure almost all gait related data directly on the feet (not in the upper part of the body as most existing wearable solutions). The platform consists of a complete tool-chain: insoles, smartphone & app, server & analysis tool, FRI estimation and user access. Results are obtained by combining parameters in a personalized way to build individual fall risk index assessed by experts with the help of data analytics. New FRI has been compared with standards that validate the quality of its prediction in a statistically significant way. That qualitatively relevant information is being provided to the platform users, being either end-users/patients, relatives or caregivers and the related clinicians to ideally assess about their long term evolution. © 2017 The authors and IOS Press.

  • 4.
    Bakowski, M
    et al.
    RISE, Swedish ICT, Acreo.
    Lim, J.-K
    RISE, Swedish ICT, Acreo.
    Kaplan, W.
    RISE, Swedish ICT, Acreo.
    Schöner, A.
    RISE, Swedish ICT, Acreo.
    Merits of buried grid technology for advanced SiC device concepts2011Ingår i: ECS Transactions, ISSN 1938-5862, E-ISSN 1938-6737, Vol. 41, nr 8, 155-162 s.Artikel i tidskrift (Refereegranskat)
  • 5.
    Bakowski, Mietek
    et al.
    RISE., Swedish ICT, Acreo.
    Lim, Jang-Kwon
    RISE., Swedish ICT, Acreo.
    Kaplan, Wlodek
    RISE., Swedish ICT, Acreo.
    Merits of Buried Grid Technology for SiC JBS Diodes2012Ingår i: GALLIUM NITRIDE AND SILICON CARBIDE POWER TECHNOLOGIES 2, 2012, 415-424 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    The SiC Schottky barrier diodes for 200 degrees C to 250 degrees C operation have been developed using buried grid (BG) technology. 2A and 10A, 1700V BG JBS diodes have been fabricated and evaluated. Manufactured 10A, 1700V BG JBS diodes have leakage current at least three orders of magnitude lower compared to the typical data sheet values of the commercial devices. The leakage current at 250 degrees C is of the same order of magnitude as that of the commercial devices at 175 degrees C. The two alternative technologies for realization of BG, implantation and epitaxy, have been compared by simulations. The epitaxial grid is shown to have superior potential for best trade-off between on-state voltage and leakage current.

  • 6.
    Bakowski, Mietek
    et al.
    RISE., Swedish ICT, Acreo.
    LIm, Jang-Kwon
    RISE., Swedish ICT, Acreo.
    Kaplan, Wlodek
    RISE., Swedish ICT, Acreo.
    Schöner, Adolf
    RISE., Swedish ICT, Acreo.
    Merits of Buried Grid Technology for Advanced SiC Device Concepts2011Ingår i: ECS Transactions, ISSN 1938-5862, E-ISSN 1938-6737, Vol. 41, nr 8, 155-162 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Some chosen examples of the use of buried grid technology for advanced SiC devices are discussed. First example is development of normally-off and normally-on JFETs. Second is the development of Schottky diodes for high temperature operation. Other examples are efficient junction termination and avalanche UV detector. Experimental results are used in support of simulations.

  • 7.
    Bender, P.
    et al.
    University of Cantabria, Spain.
    Balceris, C.
    University of Cantabria, Spain.
    Ludwig, F.
    TU Braunschweig, Germany.
    Posth, O.
    Physikalisch-Technische Bundesanstalt, Germany.
    Bogart, L. K.
    University College London, UK.
    Szczerba, W.
    Bundesanstalt für Materialforschung und -prüfung, Germany ; AGH University of Science and Technology, Poland .
    Castro, A.
    SOLVE Research and Consultancy AB, Sweden.
    Nilsson, L.
    SOLVE Research and Consultancy AB, Sweden ; Lund University, Sweden.
    Costo, R.
    Instituto de Ciencia de Materiales de Madrid, Spain.
    Gavilán, H.
    Instituto de Ciencia de Materiales de Madrid, Spain.
    González-Alonso, D.
    University of Cantabria, Spain.
    Pedro, I. D.
    University of Cantabria, Spain.
    Barquin, L. F.
    University of Cantabria, Spain.
    Johansson, C.
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Distribution functions of magnetic nanoparticles determined by a numerical inversion method2017Ingår i: New Journal of Physics, ISSN 1367-2630, E-ISSN 1367-2630, Vol. 19, nr 7, 073012Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In the present study, we applied a regularized inversion method to extract the particle size, magnetic moment and relaxation-time distribution of magnetic nanoparticles from small-angle x-ray scattering (SAXS), DC magnetization (DCM) and AC susceptibility (ACS) measurements. For the measurements the particles were colloidally dispersed in water. At first approximation the particles could be assumed to be spherically shaped and homogeneously magnetized single-domain particles. As model functions for the inversion, we used the particle form factor of a sphere (SAXS), the Langevin function (DCM) and the Debye model (ACS). The extracted distributions exhibited features/peaks that could be distinctly attributed to the individually dispersed and non-interacting nanoparticles. Further analysis of these peaks enabled, in combination with a prior characterization of the particle ensemble by electron microscopy and dynamic light scattering, a detailed structural and magnetic characterization of the particles. Additionally, all three extracted distributions featured peaks, which indicated deviations of the scattering (SAXS), magnetization (DCM) or relaxation (ACS) behavior from the one expected for individually dispersed, homogeneously magnetized nanoparticles. These deviations could be mainly attributed to partial agglomeration (SAXS, DCM, ACS), uncorrelated surface spins (DCM) and/or intra-well relaxation processes (ACS). The main advantage of the numerical inversion method is that no ad hoc assumptions regarding the line shape of the extracted distribution functions are required, which enabled the detection of these contributions. We highlighted this by comparing the results with the results obtained by standard model fits, where the functional form of the distributions was a priori assumed to be log-normal shaped.

  • 8.
    Bender, P.
    et al.
    University of Cantabria, Santander, Spain .
    Bogart, L. K.
    University College London, London, United Kingdom .
    Posth, O.
    Physikalisch-Technische Bundesanstalt, Berlin, Germany .
    Szczerba, W.
    Bundesanstalt für Materialforschung Und-prüfung (BAM), Berlin, Germany ; AGH University of Science and Technology, Krakow, Poland .
    Rogers, S. E.
    ISIS-STFC Neutron Scattering Facility, Harwell Science and Innovation Campus, Didcot, United Kingdom .
    Castro, A.
    SOLVE Research and Consultancy AB, Lund, Sweden .
    Nilsson, L.
    SOLVE Research and Consultancy AB, Lund, Sweden ; Lund University, Lund, Sweden .
    Zeng, L. J.
    Chalmers University of Technology, Göteborg, Sweden .
    Sugunan, A.
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi, material och ytor.
    Sommertune, J.
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi, material och ytor.
    Fornara, A.
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi, material och ytor.
    González-Alonso, D.
    University of Cantabria, Santander, Spain .
    Fernández Barquín, L.
    University of Cantabria, Santander, Spain .
    Johansson, C.
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Structural and magnetic properties of multi-core nanoparticles analysed using a generalised numerical inversion method2017Ingår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 7, 45990Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The structural and magnetic properties of magnetic multi-core particles were determined by numerical inversion of small angle scattering and isothermal magnetisation data. The investigated particles consist of iron oxide nanoparticle cores (9 nm) embedded in poly(styrene) spheres (160 nm). A thorough physical characterisation of the particles included transmission electron microscopy, X-ray diffraction and asymmetrical flow field-flow fractionation. Their structure was ultimately disclosed by an indirect Fourier transform of static light scattering, small angle X-ray scattering and small angle neutron scattering data of the colloidal dispersion. The extracted pair distance distribution functions clearly indicated that the cores were mostly accumulated in the outer surface layers of the poly(styrene) spheres. To investigate the magnetic properties, the isothermal magnetisation curves of the multi-core particles (immobilised and dispersed in water) were analysed. The study stands out by applying the same numerical approach to extract the apparent moment distributions of the particles as for the indirect Fourier transform. It could be shown that the main peak of the apparent moment distributions correlated to the expected intrinsic moment distribution of the cores. Additional peaks were observed which signaled deviations of the isothermal magnetisation behavior from the non-interacting case, indicating weak dipolar interactions.

  • 9.
    Brooke, Robert
    et al.
    Linköping University, Sweden.
    Mitraka, Evangelie
    Linköping University, Sweden.
    Sardar, Samim
    Linköping University, Sweden.
    Sandberg, Mats
    RISE - Research Institutes of Sweden, IKT, Acreo. Linköping University, Sweden.
    Sawatdee, Anurak
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Berggren, Magnus
    RISE - Research Institutes of Sweden, IKT, Acreo. Linköping University, Sweden.
    Crispin, Xavier
    Linköping University, Sweden.
    Jonsson, Magnus P.
    Linköping University, Sweden.
    Infrared electrochromic conducting polymer devices2017Ingår i: Journal of Materials Chemistry C, ISSN 2050-7526, E-ISSN 2050-7534, Vol. 5, nr 23, 5824-5830 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) is well known for its electrochromic properties in the visible region. Less focus has been devoted to the infrared (IR) wavelength range, although tunable IR properties could enable a wide range of novel applications. As an example, modern day vehicles have thermal cameras to identify pedestrians and animals in total darkness, but road and speed signs cannot be easily visualized by these imaging systems. IR electrochromism could enable a new generation of dynamic road signs that are compatible with thermal imaging, while simultaneously providing contrast also in the visible region. Here, we present the first metal-free flexible IR electrochromic devices, based on PEDOT:Tosylate as both the electrochromic material and electrodes. Lateral electrochromic devices enabled a detailed investigation of the IR electrochromism of thin PEDOT:Tosylate films, revealing large changes in their thermal signature, with effective temperature changes up to 10 °C between the oxidized (1.5 V) and reduced (-1.5 V) states of the polymer. Larger scale (7 × 7 cm) vertical electrochromic devices demonstrate practical suitability and showed effective temperature changes of approximately 7 °C, with good optical memory and fast switching (1.9 s from the oxidized state to the reduced state and 3.3 s for the reversed switching). The results are highly encouraging for using PEDOT:Tosylate for IR electrochromic applications.

  • 10. Camara, AR
    et al.
    Pereira, JMB
    Tarasenko, Oleksandr
    RISE, Swedish ICT, Acreo, Fiber Optics.
    Margulis, Walter
    RISE, Swedish ICT, Acreo, Fiber Optics.
    Carvalho, ICS
    Optical creation and erasure of the linear electrooptical effect in silica fiber2015Ingår i: Optics Express, ISSN 1094-4087, E-ISSN 1094-4087, Vol. 23, nr 14, 18060-18069 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We study the creation and erasure of the linear electrooptical effect in silicate fibers by optical poling. Carriers are released by exposure to green light and displaced with simultaneous application of an internal dc field. The second order nonlinear coefficient induced grows with poling bias. The field recorded (~108 V/m) is comparable to that obtained through classical thermal poling of fibers. In the regime studied here, the second-order nonlinearity induced (~0.06 pm/V) is limited by the field applied during poling (1.2 × 108 V/m). Optical erasure with high-power green light alone is very efficient. The dynamics of the writing and erasing process is discussed, and the two dimensional (2D) field distribution across the fiber is simulated.

  • 11.
    Chamania, Mohit
    et al.
    ADVA Optical Networking, Germany.
    Szyrkowiec, Thomas
    ADVA Optical Networking, Germany.
    Santuari, Michele
    CREATE-NET Research Center, Italy.
    Siracusa, Dominico
    CREATE-NET Research Center, Italy.
    Autenrieth, Achim
    ADVA Optical Networking, Germany.
    Lopez, Victor
    Telefónica I+D, Spain.
    Sköldström, Pontus
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Junique, Stephane
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Intent-based in-flight service encryption in multi-layer transport networks2017Ingår i: 2017 Optical Fiber Communications Conference and Exhibition, OFC 2017 - Proceedings, 2017Konferensbidrag (Refereegranskat)
    Abstract [en]

    We demonstrate multi-layer encrypted service provisioning via the ACINO orchestrator. ACINO combines a novel intent interface with an ONOS-based SDN orchestrator to facilitate encrypted services at IP, Ethernet and optical network layers.

  • 12.
    Cristofori, Valentina
    et al.
    Technical University of Denmark, Denmark.
    Da Ros, Francescos
    Technical University of Denmark, Denmark.
    Ozolins, Oskars
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Chaibi, Mohamed E.
    FOTON Laboratory, France.
    Bramerie, Laurent
    FOTON Laboratory, France.
    Ding, Yunhong
    Technical University of Denmark, Denmark.
    Pang, Xiadon
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Shen, Alexandre
    Thales, France.
    Gallet, Antonin
    Thales, France.
    Duan, Guang-Hua
    Thales, France.
    Hassan, Karem
    III-V Lab, France.
    Olivier, Segolene
    III-V Lab, France.
    Popov, Sergei
    KTH - Royal Institute of Technology, Sweden.
    Jacobsen, Gunnar
    Oxenløwe, Leif K.
    Technical University of Denmark, Denmark.
    Peucheret, Christophe
    FOTON Laboratory, France.
    25-Gb/s transmission over 2.5-km SSMF by silicon MRR enhanced 1.55-μm III-V/SOI DML2017Ingår i: IEEE Photonics Technology Letters, ISSN 1041-1135, E-ISSN 1941-0174, Vol. 29, nr 12, 960-963 s., 7917280Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The use of a micro-ring resonator (MRR) to enhance the modulation extinction ratio and dispersion tolerance of a directly modulated laser is experimentally investigated with a bit rate of 25 Gb/s as proposed for the next generation data center communications. The investigated system combines a 11-GHz 1.55-μm directly modulated hybrid III-V/SOI DFB laser realized by bonding III-V materials (InGaAlAs) on a silicon-on-insulator (SOI) wafer and a silicon MRR also fabricated on SOI. Such a transmitter enables error-free transmission (BER < 10-9) at 25 Gb/s data rate over 2.5-km standard single mode fiber without dispersion compensation nor forward error correction. As both laser and MRR are fabricated on the SOI platform, they could be combined into a single device with enhanced performance, thus providing a cost-effective transmitter for short reach applications.

  • 13.
    Czegledi, Christian B.
    et al.
    Chalmers University of Technology, Sweden.
    Karlsson, Magnus
    Chalmers University of Technology, Sweden.
    Johannisson, Pontus
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Agrell, Erik
    Chalmers University of Technology, Sweden.
    Temporal stochastic channel model for absolute polarization state and polarization-mode dispersion2017Ingår i: 2017 Optical Fiber Communications Conference and Exhibition, OFC 2017 - Proceedings, 2017Konferensbidrag (Refereegranskat)
    Abstract [en]

    We propose and validate a discrete-time channel model for the temporal drift of the absolute polarization state and polarization-mode dispersion for coherent fiber optic systems. The model can be used in simulations to test and develop DSP for coherent receivers.

  • 14.
    Da Ros, Francesco
    et al.
    Technical University of Denmark, Denmark.
    Cristofori, Valentina
    Technical University of Denmark, Denmark.
    Ozolins, Oskars
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Chaibi, Mohamed E.
    University of Rennes 1, France.
    Pang, Xiodan
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Jacobsen, Gunnar
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Popov, Sergei
    KTH Royal Institute of Technology, Sweden.
    Galili, Michael
    Technical University of Denmark, Denmark.
    Oxenløwe, Leif K.
    Technical University of Denmark, Denmark.
    Peucheret, Christophe
    University of Rennes 1, France.
    4-PAM dispersion-uncompensated transmission with micro-ring resonator enhanced 1.55-μm DML2017Ingår i: Optics InfoBase Conference Papers, 2017, STu1M.5.Konferensbidrag (Refereegranskat)
    Abstract [en]

    Real-time transmission of 14-GBd 4-PAM signal is demonstrated by combining a commercial 1.55-μm DML with a silicon MRR. BER below the HD-FEC threshold is measured after 26-km SSMF transmission without offline digital signal processing.

  • 15.
    D'Humières, Benoit
    et al.
    TEMATYS, France.
    Esmiller, Bruno
    Airbus Safran Launchers SAS, France.
    Gouy, Yann
    Airbus Safran Launchers SAS, France.
    Steck, Emilie
    Airbus Safran Launchers SAS, France.
    Quintana, Crisanto
    Univ. of Oxford, United Kingdom.
    Faulkner, Graham
    Univ. of Oxford, United Kingdom.
    O'Brien, Dominic
    Univ. of Oxford, United Kingdom.
    Sproll, Fabian
    Deutsches Zentrum für Luft- und Raumfahrt e.V., Germany.
    Wagner, Paul
    Deutsches Zentrum für Luft- und Raumfahrt e.V., Germany.
    Hampf, Daniel
    Deutsches Zentrum für Luft- und Raumfahrt e.V., Germany.
    Riede, Wolfgang
    Deutsches Zentrum für Luft- und Raumfahrt e.V., Germany.
    Salter, Michael
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Wang, Qin
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Platt, Duncan
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Jakonis, Darius
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Piao, Xiaoyu
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Karlsson, Mikael
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Oberg, Olof
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Petermann, Ingemar
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Michalkiewicz, Aneta
    Astri Polska Sp., Poland.
    Krezel, Jerzy
    Astri Polska Sp., Poland.
    Debowska, Anna
    Astri Polska Sp., Poland.
    Thueux, Yoann
    Airbus Group Innovations, United Kingdom.
    The C3PO project: A laser communication system concept for small satellites2017Ingår i: Proceedings of SPIE - The International Society for Optical Engineering, 2017Konferensbidrag (Refereegranskat)
    Abstract [en]

    The satellite market is shifting towards smaller (micro and nanosatellites), lowered mass and increased performance platforms. Nanosatellites and picosatellites have been used for a number of new, innovative and unique payloads and missions. This trend requires new concepts for a reduced size, a better performance/weight ratio and a reduction of onboard power consumption. In this context, disruptive technologies, such as laser-optical communication systems, are opening new possibilities. This paper presents the C3PO1 system, "advanced Concept for laser uplink/ downlink CommuniCation with sPace Objects", and the first results of the development of its key technologies. This project targets the design of a communications system that uses a ground-based laser to illuminate a satellite, and a Modulating Retro-Reflector (MRR) to return a beam of light modulated by data to the ground. This enables a downlink, without a laser source on the satellite. This architecture suits well to small satellite applications so as high data rates are potentially provided with very low board mass. C3PO project aims to achieve data rates of 1Gbit/s between LEO satellites and Earth with a communication payload mass of less than 1kilogram. In this paper, results of the initial experiments and demonstration of the key technologies will be shown.

  • 16.
    Elahipanah, H.
    et al.
    Ascatron AB, Sweden.
    Thierry-Jebali, N.
    Ascatron AB, Sweden.
    Reshanov, S. A.
    Ascatron AB, SwedenAscatron AB, Sweden.
    Kaplan, W.
    Ascatron AB, Sweden.
    Zhang, A.
    Ascatron AB, Sweden.
    Lim, J. -K
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Bakowski, M.
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Östling, M.
    KTH Royal Institute of Technology, Sweden.
    Schöner, A.
    Ascatron AB, Sweden.
    Design optimization of a high temperature 1.2 kV 4H-SiC buried grid JBS rectifier2017Ingår i: 11th European Conference on Silicon Carbide and Related Materials, ECSCRM 2016, 2017, 455-458 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    1.2 kV SiC buried grid junction barrier Schottky (BG-JBS) diodes are demonstrated. The design considerations for high temperature applications are investigated. The design is optimized in terms of doping concentration and thickness of the epilayers, as well as grid size and spacing dimensions, in order to obtain low on-resistance and reasonable leakage current even at high temperatures. The device behavior at temperatures ranging from 25 to 250ºC is analyzed and measured on wafer level. The forward voltage drop of 1.1 V at 100 A/cm2 and 3.8 V at 1000 A/cm2 is measured, respectively. At reverse voltage of 1 kV, a leakage current density below 0.1 μA/cm2 and below 0.1 mA/cm2 is measured at 25 and 250ºC, respectively. This proves the effective shielding effect of the BG-JBS design and provides benefits in high voltage applications, particularly for high temperature operation.

  • 17.
    Engelke, Ulrich
    et al.
    Commonwealth Scientific and Industrial Research Organisation, Hobart, TAS, Australia.
    Darcy, Daniel P.
    Dolby Laboratories, San Francisco, CA, USA.
    Mulliken, Grant H.
    Dolby Laboratories, San Francisco, CA, USA.
    Bosse, Sebstian
    Fraunhofer Institute for Telecommunications, Berlin, German.
    Martini, Maria G.
    Kingston University, London, U.K..
    Arndt, Sebstian
    Norwegian University of Science and Technology, Trondheim, Norway.
    Antons, Jan Niklas
    Technische Universiät Berlin, Berlin, Germany.
    Chan, Kit Y.
    Curtin University, Perth, WA, Australia.
    Ramzan, Naeem
    University of the West of Scotland, Hamilton, U.K..
    Brunnström, Kjell
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Psychophysiology-Based QoE Assessment: A Survey2017Ingår i: IEEE Journal on Selected Topics in Signal Processing, ISSN 1932-4553, E-ISSN 1941-0484, Vol. 11, nr 1, 6-21 s., 7569001Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We present a survey of psychophysiology-based assessment for quality of experience (QoE) in advanced multimedia technologies. We provide a classification of methods relevant to QoE and describe related psychological processes, experimental design considerations, and signal analysis techniques. We summarize multimodal techniques and discuss several important aspects of psychophysiology-based QoE assessment, including the synergies with psychophysical assessment and the need for standardized experimental design. This survey is not considered to be exhaustive but serves as a guideline for those interested to further explore this emerging field of research.

  • 18.
    Etcheverry, S.
    et al.
    RISE - Research Institutes of Sweden, IKT, Acreo. KTH Royal Institute of Technology, Stockholm, Sweden.
    Faridi, A.
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Ramachandraiah, H.
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Kumar, T.
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Margulis, W.
    RISE - Research Institutes of Sweden, IKT, Acreo. KTH Royal Institute of Technology, Stockholm, Sweden.
    Laurell, F.
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Russom, A.
    KTH Royal Institute of Technology, Stockholm, Sweden.
    High performance micro-flow cytometer based on optical fibres2017Ingår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 7, nr 1, 5628Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Flow cytometry is currently the gold standard for analysis of cells in the medical laboratory and biomedical research. Fuelled by the need of point-of-care diagnosis, a significant effort has been made to miniaturize and reduce cost of flow cytometers. However, despite recent advances, current microsystems remain less versatile and much slower than their large-scale counterparts. In this work, an all-silica fibre microflow cytometer is presented that measures fluorescence and scattering from particles and cells. It integrates cell transport in circular capillaries and light delivery by optical fibres. Single-stream cell focusing is performed by Elasto-inertial microfluidics to guarantee accurate and sensitive detection. The capability of this technique is extended to high flow rates (up to 800 μl/min), enabling a throughput of 2500 particles/s. The robust, portable and low-cost system described here could be the basis for a point-of-care flow cytometer with a performance comparable to commercial systems. © 2017 The Author(s).

  • 19.
    Fock, Jeppe
    et al.
    DTU Nanotech,Technical University of Denmark, Denmark .
    Jonasson, Christian
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Johansson, Christer
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Hansen, Mikkel F.
    DTU Nanotech,Technical University of Denmark, Denmark .
    Characterization of fine particles using optomagnetic measurements2017Ingår i: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 19, nr 13, 8802-8814 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The remanent magnetic moment and the hydrodynamic size are important parameters for the synthesis and applications of magnetic nanoparticles (MNPs). We present the theoretical basis for the determination of the remanent magnetic moment and the hydrodynamic size of MNPs with a narrow size distribution using optomagnetic measurements. In these, the 2nd harmonic variation of the intensity of light transmitted through an MNP suspension is measured as a function of an applied axial oscillating magnetic field. We first show how the measurements of the optomagnetic signal magnitude at a low frequency vs. magnetic field amplitude can be used to determine the MNP moment. Subsequently, we use linear response theory to describe the dynamic non-equilibrium response of the MNP suspension at low magnetic field amplitudes and derive a link between optomagnetic measurements and magnetic AC susceptibility measurements. We demonstrate the presented methodology on two samples of commercially available multi-core MNPs. The results compare well with those obtained by dynamic light scattering, AC susceptibility and vibrating sample magnetometry measurements on the same samples when the different weighting of the particle size in the techniques is taken into account. The optomagnetic technique is simple, fast and does not require prior knowledge of the concentration of MNPs and it thus has the potential to be used as a routine tool for quality control of MNPs.

  • 20.
    Forzati, Marco
    et al.
    RISE, Swedish ICT, Acreo.
    Mattson, Crister
    RISE, Swedish ICT, Acreo.
    Socio-economic return of FTTH investment in Sweden, a prestudy2014Rapport (Övrigt vetenskapligt)
    Abstract [en]

    There is a wide range of FTTH initiatives throughout Sweden, with investments made by both telecom operators and public actors. The benefits of the investments are often discussed, especially when the investment is made by municipalities or other public bodies. This preliminary study analyses the socio-economic impacts of the investment in FTTH. The goal of the study was: Is it possible to calculate how much a krona (SEK) invested in fibre will give back to society? The conclusion is that a more comprehensive statistical data and more calculations are needed to give an exact estimate. The study, however, provides an indication that 1 SEK invested over four years brings back a minimum of 1.5 SEK in five years time. The study estimates the need for investment to achieve 100% fibre penetration, identifies and quantifies a number of significant effects of fibre deployment, and then calculates the return on investment. We recommend a more extensive study, in which the proposed model is refined and expanded with more detailed and updated data. This pre-study was sponsored by the Swedish Government’s Broadband Council (Bredbandsforum).

  • 21.
    Gavilán, Helena
    et al.
    ICMM/CSIC, Madrid, Spain.
    Kowalski, Anja
    Micromod Partikeltechnologie GmbH, Rostock, Germany.
    Heinke, David
    NanoPET Pharma GmbH, Berlin, Germany.
    Sugunan, Abhilash
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi, material och ytor.
    Sommertune, Jens
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi, material och ytor.
    Varón, Miriam
    Technical University of Denmark, Kongens Lyngby, Denmark.
    Bogart, Lara K.
    University College of London, London, UK.
    Posth, Oliver
    Physikalisch-Technische Bundesanstalt, Berlin, Germany.
    Zeng, Lunjie
    Chalmers University of Technology, Gothenburg, Sweden.
    González-Alonso, David
    University of Cantabria, Santander, Spain.
    Balceris, Chrsitoph
    Institute of Electrical Measurement and Fundamental Electrical Engineering, Braunschweig, Germany.
    Fock, Jeppe
    Technical University of Denmark, Kongens Lyngby, Denmark.
    Wetterskog, Erik
    Uppsala University, Uppsala, Sweden.
    Frandsen, Cathrine
    Technical University of Denmark, Kongens Lyngby, Denmark.
    Gehrke, Nicole
    NanoPET Pharma GmbH, Berlin, Germany.
    Grüttner, Cordula
    Micromod Partikeltechnologie GmbH, Rostock, Germany.
    Fornara, Andrea
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi, material och ytor.
    Ludwig, Frank
    Institute of Electrical Measurement and Fundamental Electrical Engineering, Braunschweig, Germany.
    Veintemillas-Verdaguer, Sabino
    Instituto de Ciencia de Materiales de Madrid, ICMM/CSIC, Madrid, Spain.
    Johansson, Christer
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Morales, M. Puerto
    ICMM/CSIC, Madrid, Spain.
    Colloidal Flower-Shaped Iron Oxide Nanoparticles: Synthesis Strategies and Coatings2017Ingår i: Particle & particle systems characterization, ISSN 0934-0866, E-ISSN 1521-4117, Vol. 34, nr 7, 1700094Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The assembly of magnetic cores into regular structures may notably influence the properties displayed by a magnetic colloid. Here, key synthesis parameters driving the self-assembly process capable of organizing colloidal magnetic cores into highly regular and reproducible multi-core nanoparticles are determined. In addition, a self-consistent picture that explains the collective magnetic properties exhibited by these complex assemblies is achieved through structural, colloidal, and magnetic means. For this purpose, different strategies to obtain flower-shaped iron oxide assemblies in the size range 25–100 nm are examined. The routes are based on the partial oxidation of Fe(OH)2, polyol-mediated synthesis or the reduction of iron acetylacetonate. The nanoparticles are functionalized either with dextran, citric acid, or alternatively embedded in polystyrene and their long-term stability is assessed. The core size is measured, calculated, and modeled using both structural and magnetic means, while the Debye model and multi-core extended model are used to study interparticle interactions. This is the first step toward standardized protocols of synthesis and characterization of flower-shaped nanoparticles.

  • 22. Gerosa, RM
    et al.
    Sudirman, Aziza
    RISE, Swedish ICT, Acreo, Fiber Optics.
    Menezes, LdS
    Margulis, Walter
    RISE, Swedish ICT, Acreo, Fiber Optics.
    de Matos, CJS
    All-fiber high repetition rate dye laser2015Ingår i: Optical Society of America. Journal A: Optics, Image Science, and Vision, ISSN 1084-7529, E-ISSN 1520-8532, Vol. 2, nr 2, 186-193 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Optofluidic dye lasers may play a significant role in future laser applications in numerous areas, combining wavelength flexibility with integration and ease of operation. Nevertheless, no all-fiber integrated dye lasers have been demonstrated so far. In this paper, we report on a series of optofluidic all-fiber Rhodamine optical sources operating at a repetition rate as high as 1 kHz. Dye bleaching is avoided by circulating the Rhodamine dye during optical excitation. The laser radiation is extracted via conventional fibers that are spliced to the dye-filled capillary active medium. A tuneable amplified spontaneous emission source, a multimode laser, and a few transverse-mode laser are demonstrated by adjusting the setup. Threshold pump energies as low as similar to 1 mu J and slope efficiencies of up to mu 9% were obtained, indicating the potential for realworld applications in areas such as spectroscopy and biomedicine.

  • 23.
    Golabi, Mohsen
    et al.
    Linköping University, Linköping, Sweden.
    Kuralay, Filiz
    Ordu University, Ordu, Turkey.
    Jager, Edwin W. H.
    Linköping University, Linköping, Sweden.
    Beni, Valerio
    RISE - Research Institutes of Sweden, IKT, Acreo. Linköping University, Linköping, Sweden.
    Turner, Anthony P. F.
    Linköping University, Linköping, Sweden.
    Electrochemical bacterial detection using poly(3-aminophenylboronic acid)-based imprinted polymer2017Ingår i: Biosensors & bioelectronics, ISSN 0956-5663, E-ISSN 1873-4235, Vol. 93, 87-93 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Biosensors can deliver the rapid bacterial detection that is needed in many fields including food safety, clinical diagnostics, biosafety and biosecurity. Whole-cell imprinted polymers have the potential to be applied as recognition elements in biosensors for selective bacterial detection. In this paper, we report on the use of 3-aminophenylboronic acid (3-APBA) for the electrochemical fabrication of a cell-imprinted polymer (CIP). The use of a monomer bearing a boronic acid group, with its ability to specifically interact with cis-diol, allowed the formation of a polymeric network presenting both morphological and chemical recognition abilities. A particularly beneficial feature of the proposed approach is the reversibility of the cis-diol-boronic group complex, which facilitates easy release of the captured bacterial cells and subsequent regeneration of the CIP. Staphylococcus epidermidis was used as the model target bacteria for the CIP and electrochemical impedance spectroscopy (EIS) was explored for the label-free detection of the target bacteria. The modified electrodes showed a linear response over the range of 103–107 cfu/mL. A selectivity study also showed that the CIP could discriminate its target from non-target bacteria having similar shape. The CIPs had high affinity and specificity for bacterial detection and provided a switchable interface for easy removal of bacterial cell.

  • 24.
    Gurell, Jonas
    et al.
    RISE, Swerea, Swerea KIMAB AB.
    Bengtson, Arne
    RISE, Swerea, Swerea KIMAB AB.
    Falkenström, Magnus
    RISE, Swerea, Swerea KIMAB AB.
    Hansson, B.A.M.
    Acreo AB.
    Laser induced breakdown spectroscopy for fast elemental analysis and sorting of metallic scrap pieces using certified reference materials2012Ingår i: Spectrochimica Acta Part B - Atomic Spectroscopy, ISSN 0584-8547, E-ISSN 1873-3565, Vol. 74-75, 46-50 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A setup utilizing laser induced breakdown spectroscopy (LIBS) for performing elemental analysis in order to classify metallic samples is currently under construction. The setup uses short laser pulses to locally ablate the sample and create luminous plasmas. The emitted light is analyzed spectroscopically for instantaneous determination of the elemental composition. A table-top system based on a compact CCD spectrometer has been constructed and combined with fast software in order to test the concept of remote, single shot material classification with LIBS. Certified reference materials with known elemental compositions were used in the laboratory tests. We report on successful laboratory tests in which samples were classified using an analysis based on optical emission following a single laser pulse and with an operating distance of approximately 1 m. Details regarding field tests of this versatile and promising technique are discussed. © 2012 Elsevier B.V.

  • 25.
    Hong, Xuezhi
    et al.
    KTH Royal Institute of Technology, Sweden ; South China Normal University, China.
    Ozolins, Oskars
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Guo, Changjian
    South China Normal University, China.
    Pang, Xiaodan
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Zhang, Junwei
    South China Normal University, China.
    Navarro, Jaime R.
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Kakkar, Aditya
    KTH Royal Institute of Technology, Sweden.
    Schatz, Richard
    KTH Royal Institute of Technology, Sweden.
    Westergren, Urban
    KTH Royal Institute of Technology, Sweden.
    Jacobsen, Gunnar
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Popov, Sergei
    KTH Royal Institute of Technology, Sweden.
    Chen, Jiajia
    South China Normal University, China ; KTH Royal Institute of Technology, Sweden.
    1.55-µm EML-based DMT Transmission with Nonlinearity-Aware Time Domain Super-Nyquist Image Induced Aliasing2017Konferensbidrag (Refereegranskat)
    Abstract [en]

    We experimentally demonstrate a DMT transmission system with 1.55-µm EML using nonlinearity-aware time domain super-Nyquist image induced aliasing. Compared with linear equalization, the capacity is improved by ~16.8%(33.1%) with proposed method for 4(40) km transmission.

  • 26.
    Hultin, Olof
    et al.
    Lund University, Lund, Sweden.
    Otnes, Gautne
    Lund University, Lund, Sweden.
    Samuelson, Lars
    Lund University, Lund, Sweden.
    Storm, Karin
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Simplifying Nanowire Hall Effect Characterization by Using a Three-Probe Device Design2017Ingår i: Nano letters (Print), ISSN 1530-6984, E-ISSN 1530-6992, Vol. 17, nr 2, 1121-1126 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Electrical characterization of nanowires is a time-consuming and challenging task due to the complexity of single nanowire device fabrication and the difficulty in interpreting the measurements. We present a method to measure Hall effect in nanowires using a three-probe device that is simpler to fabricate than previous four-probe nanowire Hall devices and allows characterization of nanowires with smaller diameter. Extraction of charge carrier concentration from the three-probe measurements using an analytical model is discussed and compared to simulations. The validity of the method is experimentally verified by a comparison between results obtained with the three-probe method and results obtained using four-probe nanowire Hall measurements. In addition, a nanowire with a diameter of only 65 nm is characterized to demonstrate the capabilities of the method. The three-probe Hall effect method offers a relatively fast and simple, yet accurate way to quantify the charge carrier concentration in nanowires and has the potential to become a standard characterization technique for nanowires.

  • 27.
    Hyllander, G.
    et al.
    Loussavaara-Kiirunavaara AB (LKAB).
    Ökvist, Lena Sundqvist
    Swerea Mefos AB.
    Malmberg, David
    RISE, Swerea, Swerea MEFOS AB.
    Eriksson, Johan
    RISE, Swerea, Swerea MEFOS AB.
    Olsson, E.
    SSAB EMEA AB.
    Zetterlund, E.
    Acreo AB.
    Tarasenko, O.
    Acreo AB.
    Innovative measurement technique for raceway monitoring2012Ingår i: 6th Int. Congress on the Science and Technology of Ironmaking 2012, ICSTI 2012 - Including Proceedings from the 42nd Ironmaking and Raw Materials Seminar, and the 13th Brazilian Symp. on Iron Ore, 2012, Vol. 3, 1732-1743 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    When raceway conditions are changed, e.g blast parameters or selection of injection material, additional measurements and monitoring of raceway can support evaluation of the effects on raceway conditions. Two types of measurement methods have been tested during injection trials with BF flue dust at the SSAB EMEA BF in Oxelösund and the LKAB Experimental Blast Furnace (EBF®). The raceway depth was measured using microwave technique and a camera was installed for viewing the raceway when the peep hole was occupied by the depth measurements equipment. Temperature estimation was made on thermal radiation guided via an optical fibre from the raceway to a spectrometer. Evaluation methods were developed based on Planck radiation law. The measurement techniques and their use for monitoring of raceway conditions are discussed.

  • 28. Jason, Johan
    et al.
    Rugeland, Patrik
    RISE, Swedish ICT, Acreo.
    Tarasenko, Oleksandr
    RISE, Swedish ICT, Acreo.
    Margulis, Walter
    RISE, Swedish ICT, Acreo.
    Nilsson, Hans-Erik
    Temperature characteristics of the birefringence properties of filled side-hole fibers.2013Ingår i: Applied Optics, ISSN 0003-6935, E-ISSN 1539-4522, Vol. 52, nr 21, 5208-5215 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The temperature characteristics of the birefringence of side-hole fibers filled with liquids or metal are investigated, aiming at providing a basis for on/off temperature sensing. Short pieces of fiber are filled and the change in birefringence is registered using measurements in reflective mode of the transmitted power through a linear polarizer at 1550 nm. The rapid change in the birefringence behavior of the fiber at the temperature of the phase transition of the filler substance is shown, and from the measurement data the phase transition temperatures can be determined as well as an estimation of the birefringence change with temperature. The experimental results are supported by numerical simulations.

  • 29.
    Johansson, Christer
    et al.
    RISE, Swedish ICT, Acreo, Sensor Systems.
    Ahrentorp, Fredrik
    Metod och anordning för detektering av förändringar av magnetisk respons hos magnetiska partiklar försedda med yttre skikt i bärarvätska2002Patent (Övrig (populärvetenskap, debatt, mm))
  • 30.
    John, Wolfgang
    et al.
    Ericsson AB, Kista, Sweden.
    Marchetto, Guido
    Politecnico di Torino, Italy.
    Németh, Felician
    Budapest University of Technology and Economics, Budapest, Hungary.
    Sköldström, Pontus
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Steinert, Rebecca
    RISE - Research Institutes of Sweden, IKT, SICS.
    Meirosu, Catalin
    Ericsson AB, Kista, Sweden.
    Papafili, Ioanna
    Hellenic Telecommunications Organization, Greece.
    Pentikousis, Kostas
    Travelping, Berlin, Germany.
    Service provider DevOps2017Ingår i: IEEE Communications Magazine, ISSN 0163-6804, E-ISSN 1558-1896, Vol. 55, nr 1, 204-211 s., 7823363Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Although there is consensus that software defined networking and network functions virtualization overhaul service provisioning and deployment, the community still lacks a definite answer on how carrier-grade operations praxis needs to evolve. This article presents what lies beyond the first evolutionary steps in network management, identifies the challenges in service verification, observability, and troubleshooting, and explains how to address them using our Service Provider DevOps (SP-DevOps) framework. We compendiously cover the entire process from design goals to tool realization and employ an elastic version of an industry-standard use case to show how on-the-fly verification, software-defined monitoring, and automated troubleshooting of services reduce the cost of fault management actions. We assess SP-DevOps with respect to key attributes of software-defined telecommunication infrastructures both qualitatively and quantitatively, and demonstrate that SP-DevOps paves the way toward carrier-grade operations and management in the network virtualization era.

  • 31. Kakkar, A.
    et al.
    Navarro, J. R.
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Schatz, R.
    Louchet, H.
    Pang, X.
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Ozolins, O.
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Jacobsen, G.
    Popov, S.
    Comprehensive Study of Equalization-Enhanced Phase Noise in Coherent Optical Systems2015Ingår i: Journal of Lightwave Technology, ISSN 0733-8724, E-ISSN 1558-2213, Vol. 33, nr 23, 4834-4841 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A thorough analysis of equalization-enhanced phase noise (EEPN) and its impact on the coherent optical system is presented. We show with a time-domain analysis that EEPN is caused due to the interference of multiple delayed versions of the dispersed signal, generated by intermixing of the received dispersed signal, and the noise side bands of the local oscillator (LO) in the photodetectors. We derive statistical properties such as the mean, variance, and error vector magnitude of the received signal influenced with EEPN. We show that in coherent optical systems utilizing electronic dispersion compensation, this noise corresponds to multipath fading in wireless communication systems. Closed-form expressions of necessary LO linewidth and/or mitigation bandwidth for a general system configuration and specified OSNR penalty are given. The expressions for system design parameters, validated with system simulations, show that higher order modulation formats, such as 16-quadrature amplitude modulation and beyond, put stringent demands on the LO linewidth unless a mitigation technique is used.

  • 32. Kakkar, A.
    et al.
    Navarro, J. R.
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Schatz, R.
    Pang, X.
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Ozolins, O.
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Louchet, H.
    Jacobsen, G.
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Popov, S.
    Mitigation of EEPN in Coherent Optical Systems With Low-Speed Digital Coherence Enhancement2015Ingår i: IEEE Photonics Technology Letters, ISSN 1041-1135, E-ISSN 1941-0174, Vol. 27, nr 18, 1942-1945 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A method for mitigating local oscillator (LO) phase noise-induced impairment, also known as equalization-enhanced phase noise, in coherent optical systems is discussed. The method is suitable for real-time implementation and requires hardware with a bandwidth much lower than the signal baud rate, even for a system utilizing conventional semiconductor laser as LO. We evaluate the required parameters like interpolation technique, electrical signal-to-noise ratio at digital coherence enhancement (DCE) front end, for long haul transmission links having quadrature phase shift keying and 16-quadrature amplitude modulation formats. We show that the method can be implemented using a low-speed DCE front end and a simple digital linear interpolator with small (<;1 dB) implementation penalty even in cases that would otherwise result in error floor.

  • 33. Kakkar, A.
    et al.
    Ozolins, O.
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Navarro, J. R.
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Pang, X.
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Olmedo, M. I.
    Schatz, R.
    Louchet, H.
    Jacobsen, G.
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Popov, S.
    Design of coherent optical systems impaired by EEPN2016Ingår i: 2016 Optical Fiber Communications Conference and Exhibition (OFC), 2016, paper Tu2A.2Konferensbidrag (Refereegranskat)
    Abstract [en]

    We present experimental validation of novel analytical expressions essential for the design of coherent optical systems impaired by EEPN. These expressions enable a simple and accurate EEPN analysis for any system specification.

  • 34. Kakkar, A.
    et al.
    Pang, X.
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Ozolins, O.
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Schatz, R.
    Navarro, J. R.
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Louchet, H.
    Jacobsen, G.
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Popov, S.
    A path to use large linewidth LO in 28 Gbd 16-QAM metro links2015Ingår i: 2015 European Conference on Optical Communication (ECOC), 2015, 1-3 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    We experimentally investigate the possibility to mitigate local oscillator induced Equalization Enhanced Phase Noise penalty. The results pave the way for the use of even 10 MHz linewidth local oscillator lasers in 28 Gbd 16-QAM metro links.

  • 35.
    Kakkar, Aditya
    et al.
    KTH Royal Institute of Technology, Sweden.
    Navarro, Jaime Rodrigo
    KTH Royal Institute of Technology, Sweden.
    Pang, Xiaodan
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Ozolins, Oskars
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Schatz, Richard
    KTH Royal Institute of Technology, Sweden.
    Westergren, Urban
    KTH Royal Institute of Technology, Sweden.
    Jacobsen, Gunnar
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Popov, Sergei
    KTH Royal Institute of Technology, Sweden.
    Low complexity timing recovery algorithm for PAM-8 in high speed direct detection short range links2017Ingår i: 2017 Optical Fiber Communications Conference and Exhibition, OFC 2017 - Proceedings, 2017Konferensbidrag (Refereegranskat)
    Abstract [en]

    We propose a low complexity timing algorithm for high order PAM. Experimental results demonstrate higher performance and lower complexity than conventional algorithms in a 32 Gbaud PAM-8 transmission over 4 km SMF links.

  • 36.
    Kakkar, Aditya
    et al.
    KTH Royal Institute of Technology, Sweden.
    Navarro, Jaime Rodrigo
    KTH Royal Institute of Technology, Sweden.
    Schatz, Richard
    KTH Royal Institute of Technology, Sweden.
    Pang, Xiaodan
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Ozolins, Oskars
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Nordwall, Fredrik
    Tektronix GmbH, Germany.
    Zibar, Darko
    Technical University of Denmark, Denmark.
    Jacobsen, Gunnar
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Popov, Sergei
    KTH Royal Institute of Technology, Sweden.
    Influence of lasers with non-white frequency noise on the design of coherent optical links2017Ingår i: 2017 Optical Fiber Communications Conference and Exhibition, OFC 2017 - Proceedings, 2017Konferensbidrag (Refereegranskat)
    Abstract [en]

    We experimentally demonstrate for a 28 Gbaud 64-QAM metro link that the LO frequency noise causes timing impairment. Results show the existence of LO frequency noise spectrum regimes where different design criteria apply.

  • 37.
    Kalashnikov, Vladimir
    et al.
    Aston University, Birmingham, UK ; Vienna University of Technology, Vienna, Austria.
    Sergeyev, Sergey V.
    Aston University, Birmingham, UK.
    Ania-Castanón, Juan Diego
    Instituto de Optica CSIC, Madrid, Spain.
    Jacobsen, Gunnar
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Popov, Sergei
    Royal Institute of Technology (KTH), Stockholm, Sweden.
    Stochastic phenomena in a fiber Raman amplifier2017Ingår i: Annalen der Physik, ISSN 0003-3804, E-ISSN 1521-3889, Vol. 529, nr 1-2, 1600238Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The interplay of such cornerstones of modern nonlinear fiber optics as a nonlinearity, stochasticity and polarization leads to variety of the noise induced instabilities including polarization attraction and escape phenomena harnessing of which is a key to unlocking the fiber optic systems specifications required in high resolution spectroscopy, metrology, biomedicine and telecommunications. Here, by using direct stochastic modeling, the mapping of interplay of the Raman scattering-based nonlinearity, the random birefringence of a fiber, and the pump-to-signal intensity noise transfer has been done in terms of the fiber Raman amplifier parameters, namely polarization mode dispersion, the relative intensity noise of the pump laser, fiber length, and the signal power. The obtained results reveal conditions for emergence of the random birefringence-induced resonance-like enhancement of the gain fluctuations (stochastic anti-resonance) accompanied by pulse broadening and rare events in the form of low power output signals having probability heavily deviated from the Gaussian distribution. (Figure presented.).

  • 38.
    Keshmiri, Vahid
    et al.
    Linköping University, Sweden.
    Westerberg, David
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Andersson Ersman, Peter
    RISE - Research Institutes of Sweden, IKT.
    Sandberg, Mats
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Forchheimer, Robert
    Linköping University, Sweden.
    Tu, Deyu
    Linköping University, Sweden.
    A Silicon-Organic Hybrid Voltage Equalizer for Supercapacitor Balancing2017Ingår i: IEEE Journal on Emerging and Selected Topics in Circuits and Systems, ISSN 2156-3357, Vol. 7, nr 1, 114-122 s., 7817802Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Cell voltage equalizers are an important part in electric energy storage systems comprising series-connected cells, for example, supercapacitors. Hybrid electronics with silicon chips and printed devices enables electronic systems with moderate performance and low cost. This paper presents a silicon-organic hybrid voltage equalizer to balance and protect series-connected supercapacitor cells during charging. Printed organic electrochemical transistors with conducting polymer poly(3,4-ethylenedioxythiophene): poly(styrene sulfonate) (PEDOT:PSS) are utilized to bypass excess current when the supercapacitor cells are fully charged to desired voltages. In this study, low-cost silicon microcontrollers (ATtiny85) are programmed to sense voltages across the supercapacitor cells and control the organic electrochemical transistors to bypass charging current when the voltages exceed 1 V. Experimental results show that the hybrid equalizer with the organic electrochemical transistors works in dual-mode, switched-transistor mode or constant-resistor mode, depending on the charging current applied (0.3-100 mA). With the voltage equalizer, capacitors are charged equally regardless of their capacitances. This work demonstrates a low-cost hybrid solution for supercapacitor balancing modules at large-scale packs.

  • 39.
    Krismer, Florian
    et al.
    Swiss Federal Institute of Technology, Zurich, Switzerland.
    Schroth, Sebastian
    ebm-papst Mulfingen GmbH & Co. KG, Mulfingen, Germany.
    Ertl, Hans
    Vienna University of Technology, Wien, Austria.
    Kostov, Konstantin Stoychev
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Nee, Hans-Peter
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Kolar, Johann Walter
    Swiss Federal Institute of Technology, Zurich, Switzerland.
    Analysis and practical relevance of CM/DM EMI noise separator characteristics2017Ingår i: IEEE transactions on power electronics, ISSN 0885-8993, E-ISSN 1941-0107, Vol. 32, nr 4, 3112-3127 s., 7488180Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This work investigates sources of measurement errors that result for common mode/differential mode (CM/DM) separators in a practical measurement environment, with a particular focus on the recently presented input impedance criterion for CM/DM separators, derives the respective analytical expressions, and employs a detailed analytical model to verify the obtained findings. Furthermore, a method is derived, which determines the worst-case measurement error by reason of cross coupling for given measured DM and CM output voltage components. Based on an example, this work illustrates how the obtained expressions can be advantageously used in a computer program to automatically decide whether a particular spectral measurement component represents a useful measurement result or if it is strongly affected by cross coupling (CM to DM and DM to CM). Finally, the paper presents the realization and accompanying experimental results of an active CM/DM separator, which allows for low realization effort and features competitive separation capabilities (DMTR/CMRR > 50 dB and CMTR/DMRR > 42 dB for frequencies up to 10 MHz).

  • 40.
    Lang, J.
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut.
    Lim, J-K
    RISE., Swedish ICT, Acreo.
    Hellén, J.
    Nilsson, T. M. J.
    Schodt, B.
    RISE., SP – Sveriges Tekniska Forskningsinstitut.
    Poder, R.
    RISE., SP – Sveriges Tekniska Forskningsinstitut.
    Belov, I.
    Bakowski, Mietek
    RISE., Swedish ICT, Acreo.
    Leisner, P.
    RISE., SP – Sveriges Tekniska Forskningsinstitut.
    Reliability study of a RF power amplifier with GaN-on-SiC HEMTs2016Ingår i: ECS Transactions, 2016, nr 12, 49-59 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    RF power amplifier demonstrators containing each one GaN-on- SiC, HEMT, CHZ015A-QEG, from UMS in SMD quad-flat noleads package (QFN) were subjected to thermal cycles (TC) and power cycles (PC) and evaluated electrically, thermally and structurally. Two types of lead-free solders (Sn63Pb36Ag2 and SnAgCu (SAC305)) and two types of TIM materials (NanoTIM and TgonTM 805) for PCB attachment to liquid cold plate were tested for thermo-mechanical reliability. Changes in electrical performance of the devices namely reduction of the current saturation value, threshold voltage shift, increase of the leakage current and degradation of the HF performance were observed as a result of an accumulated current stress during PC. No significant changes in the investigated solder or TIM materials were observed. © The Electrochemical Society.

  • 41.
    Leong, Miu Y.
    et al.
    RISE - Research Institutes of Sweden, IKT, Acreo. KTH Royal Institute of Technology, Stockholm, Sweden.
    Larsen, Knud J.
    Technical University of Denmark (DTU), Kgs. Lyngby, Denmark.
    Jacobsen, Gunnar
    RISE - Research Institutes of Sweden, IKT, Acreo. KTH Royal Institute of Technology, Stockholm, Sweden.
    Zibar, Darko
    Technical University of Denmark (DTU), Kgs. Lyngby, Denmark.
    Sergeyev, Sergey
    Aston University, Birmingham, UK.
    Popov, Sergei
    KTH Royal Institute of Technology, Stockholm, Sweden.
    BCH Codes for Coherent Star DQAM Systems with Laser Phase Noise2017Ingår i: Journal of optical communications, ISSN 0173-4911, E-ISSN 2191-6322, Vol. 38, nr 1, 47-56 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Coherent optical systems have relatively high laser phase noise, which affects the performance of forward error correction (FEC) codes. In this paper, we propose a method for selecting Bose-Chaudhuri-Hocquenghem (BCH) codes for coherent systems with star-shaped constellations and M-ary differential quadrature amplitude modulation (DQAM). Our method supports constellations of any order M which is a power of 2, and includes differential M-ary phase shift keying as a special case. Our approach is straightforward, requiring only short pre-FEC simulations to parameterize a statistical model, based on which we select codes analytically. It is applicable to pre-FEC bit error rates (BERs) of around 10-3. We evaluate the accuracy of our approach using numerical simulations. For a target post-FEC BER of 10-5, codes selected with our method yield BERs within 2× target. Lastly, we extend our method to systems with interleaving, which enables us to use codes with lower overhead.

  • 42.
    Leong, Miu Yoong
    et al.
    RISE., Swedish ICT, Acreo. KTH, Optik och Fotonik, OFO.
    Larsen, Knud J.
    Jacobsen, Gunnar
    RISE., Swedish ICT, Acreo. KTH, Optik och Fotonik, OFO.
    Popov, Sergei
    KTH, Optik och Fotonik, OFO.
    Zibar, Darko
    Sergeyev, Sergey
    Interleavers and BCH Codes for Coherent DQPSK Systems With Laser Phase Noise2015Ingår i: IEEE Photonics Technology Letters, ISSN 1041-1135, E-ISSN 1941-0174, Vol. 27, nr 7, 685-688 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The relatively high phase noise of coherent optical systems poses unique challenges for forward error correction (FEC). In this letter, we propose a novel semianalytical method for selecting combinations of interleaver lengths and binary Bose-Chaudhuri-Hocquenghem (BCH) codes that meet a target post-FEC bit error rate (BER). Our method requires only short pre-FEC simulations, based on which we design interleavers and codes analytically. It is applicable to pre-FEC BER similar to 10(-3), and any post-FEC BER. In addition, we show that there is a tradeoff between code overhead and interleaver delay. Finally, for a target of 10(-5), numerical simulations show that interleaver-code combinations selected using our method have post-FEC BER around 2x target. The target BER is achieved with 0.1 dB extra signal-to-noise ratio.

  • 43.
    Leong, Miu Yoong
    et al.
    RISE - Research Institutes of Sweden, IKT, Acreo. KTH Royal Institute of TechnologyStockholmSweden.
    Larsen, Knud J.
    Technical University of Denmark (DTU)Kgs,. Lyngby, Denmark.
    Jacobsen, Gunnar
    RISE - Research Institutes of Sweden, IKT, Acreo. KTH Royal Institute of Technology, Stockholm, Sweden.
    Zibar, Darko
    Technical University of Denmark (DTU)Kgs. Lyngby, Denmark.
    Sergeyev, Sergey
    Aston University, Birmingham, UK.
    Popov, Sergei
    KTH Royal Institute of TechnologyStockholmSweden.
    Low-complexity BCH codes with optimized interleavers for DQPSK systems with laser phase noise2017Ingår i: Photonic network communications, ISSN 1387-974X, E-ISSN 1572-8188, Vol. 33, nr 3, 328-333 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The presence of high phase noise in addition to additive white Gaussian noise in coherent optical systems affects the performance of forward error correction (FEC) schemes. In this paper, we propose a simple scheme for such systems, using block interleavers and binary Bose–Chaudhuri–Hocquenghem (BCH) codes. The block interleavers are specifically optimized for differential quadrature phase shift keying modulation. We propose a method for selecting BCH codes that, together with the interleavers, achieve a target post-FEC bit error rate (BER). This combination of interleavers and BCH codes has very low implementation complexity. In addition, our approach is straightforward, requiring only short pre-FEC simulations to parameterize a model, based on which we select codes analytically. We aim to correct a pre-FEC BER of around 10 - 3. We evaluate the accuracy of our approach using numerical simulations. For a target post-FEC BER of 10 - 6, codes selected using our method result in BERs around 3× target and achieve the target with around 0.2 dB extra signal-to-noise ratio.

  • 44.
    Lim, Jang-Kwon
    et al.
    RISE., Swedish ICT, Acreo, Nanoteknologi.
    Peftitsis, Dimosthenis
    KTH, Elektrisk energiomvandling.
    Rabkowski, Jacek
    KTH, Elektrisk energiomvandling.
    Bakowski, Mietek
    RISE., Swedish ICT, Acreo, Nanoteknologi.
    Nee, Hans-Peter
    KTH, Elektrisk energiomvandling.
    Analysis and Experimental Verification of the Influence of Fabrication Process Tolerances and Circuit Parasitics on Transient Current Sharing of Parallel-Connected SiC JFETs2014Ingår i: IEEE transactions on power electronics, ISSN 0885-8993, E-ISSN 1941-0107, Vol. 29, nr 5, 2180-2191 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Operation of parallel-connected 4H-SiC vertical junction field effect transistors (VJFETs) from SemiSouth is modeled using numerical simulations and experimentally verified. The unbalanced current waveforms of parallel-connected VJFETs are investigated with respect to the spread in the critical parameters of the device structure and to the influence of the parasitic inductances in the measurement circuit. The device structures are reconstructed based on scanning electron microscopy (SEM) analysis, electrical characterization, and device simulations. The doping concentration and profile depth of a p-grid formed by angular implantation are studied as main contributors that influence the variation of the on-state characteristics, and the threshold voltage of the experimental devices. It has been shown elsewhere that similar differences in p-grid also lead to differences in gate-source breakdown voltage. The switching performance of the parallel-connected JFETs is measured using single and double gate drivers in a double-pulse test and compared with simulations. The switched current and voltage waveforms from measurements are reproduced in simulation by introducing the parasitics. From the analysis, it is found that reasonable differences in doping levels and profiles of the p-grid give rise to significant differences in device parameters. However, even with these parameter differences and circuit asymmetries, it is possible to successfully operate parallel-connected VJFETs of this type.

  • 45.
    Lim, Jang-Kwon
    et al.
    RISE., Swedish ICT, Acreo.
    Peftitsis, Dimosthenis
    KTH, Elektrisk energiomvandling.
    Rabkowski, Jacek
    KTH, Elektrisk energiomvandling.
    Bakowski, Mietek
    RISE., Swedish ICT, Acreo.
    Nee, Hans-Peter
    KTH, Elektrisk energiomvandling.
    Modeling of the impact of parameter spread on the switching performance of parallel-connected SiC VJFETs2013Ingår i: Materials Science Forum, Trans Tech Publications Inc. , 2013, 1098-1102 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    Operation of parallel-connected 4H-SiC VJFETs from SemiSouth was measured and modeled using numerical simulations. The unbalanced current waveforms in parallel-connected VJFETs were related to spread in the critical parameters of the device structure and to the influence of the parasitic inductances in the measurement circuit. The physical device structure was reconstructed based on SEM analysis, electrical characterization, and device simulations. The two hypothetical critical design parameters that were studied with respect to spread were the p-gate doping profile (Case 1) and the emitter doping (Case 2). Variation in both parameters could be related to variation in the emitter breakdown voltage, the on-state characteristics, and the threshold voltage of the experimental devices. The switching performance of the parallel-connected JFETs was measured using a single gate driver in a double pulse test and compared with simulations. In both investigated cases a very good agreement between measurements and simulations was obtained. The modeling of the transient performance relies on good reproduction of transfer characteristics and circuit parasitics.

  • 46.
    Lim, Jang-Kwon
    et al.
    RISE., Swedish ICT, Acreo. KTH, Mikro- och nanosystemteknik.
    Peftitsis, Dimosthenis
    KTH, Skolan för elektro- och systemteknik (EES).
    Sadik, Diane-Perle
    KTH, Skolan för elektro- och systemteknik (EES).
    Bakowski, Mietek
    RISE., Swedish ICT, Acreo.
    Nee, Hans-Peter
    KTH, Elektrisk energiomvandling.
    Evaluation of buried grid JBS diodes2014Ingår i: 15th International Conference on Silicon Carbide and Related Materials, ICSCRM 2013, Trans Tech Publications Inc. , 2014, 804-807 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    The 4H-SiC Schottky barrier diodes for high temperature operation over 200 °C have been developed using buried grids formed by implantation. Compared to a conventional JBS-type SBD with surface grid (SG), JBS-type SBD with buried grid (BG) has significantly reduced leakage current at reverse bias due to a better field shielding of the Schottky contact. By introducing the BG technology, the 1.7 kV diodes with an anode area 0.0024 cm2 (1 A) and 0.024 cm2 (10 A) were successfully fabricated, encapsulated in TO220 packages, and electrically evaluated. Two types of buried grid arrangement with different grid spacing dimensions were investigated. The measured IV characteristics were compared with simulation. The best fit was obtained with an active area of approximately 60% and 70% of the anode area in large and small devices, respectively. The measured values of the device capacitances were 1000 pF in large devices and 100 pF in small devices at zero bias. The capacitance values are proportional to the device area. The recovery behavior of big devices was measured in a double pulse tester and simulated. The recovery charge, Qc, was 18 nC and 24 nC in simulation and measurement, respectively. The fabricated BG JBS-type SBDs have a smaller maximum reverse recovery current compared to the commercial devices. No influence of the different grid spacing on the recovery charge was observed.

  • 47.
    Lim, Jang-Kwon
    et al.
    RISE., Swedish ICT, Acreo. KTH, Elektrisk energiomvandling.
    Östlund, Ludwig
    RISE., Swedish ICT, Acreo.
    Wang, Qin
    RISE., Swedish ICT, Acreo.
    Kaplan, Wlodek
    RISE., Swedish ICT, Acreo.
    Reshanov, Sergey A.
    RISE., Swedish ICT, Acreo.
    Schöner, Adolf
    RISE., Swedish ICT, Acreo.
    Bakowski, Mietek
    RISE., Swedish ICT, Acreo.
    Nee, Hans-Peter
    RISE., Swedish ICT, Acreo. KTH, Elektrisk energiomvandling.
    A theoretical and experimental comparison of 4H- and 6H-SiC MSM UV photodetectors2012Ingår i: Silicon Carbide and Related Materials 2011, Trans Tech Publications Inc. , 2012, 1207-1210 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper reports on fabrication and modeling of 4H- and 6H-SiC metal-semiconductor-metal (MSM) photodetectors (PDs). MSM PDs have been fabricated on 4H-SiC and 6H-SiC epitaxial layers, and their performance analyzed by MEDICI simulation and measurements. The simulations were also used to optimize the sensitivity by varying the width and spacing of the interdigitated electrodes. The fabricated PDs with 2 ÎŒm wide metal electrodes and 3 ÎŒm spacing between the electrodes exhibited, under UV illumination, a peak current to dark current ratio of 10 5 and 10 4 in 4H-SiC and 6H-SiC, respectively. The measured spectral responsivity of 6H-SiC PDs was higher compared to that of 4H-SiC PDs, with a cutoff at 407 nm compared to 384 nm in 4H-SiC PDs. Also the peak responsivity occurred at a shorter wavelength in 6H material. A high rejection ratio between the photocurrent and dark current was found in both cases. These experimental results were in agreement with simulation.

  • 48.
    Lobov, Gleb S.
    et al.
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Marinins, Aleksandrs
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Etcheverry, Sebastian
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Zhao, Yichen
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Vasileva, Elena
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Sugunan, Abhilash
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi, material och ytor.
    Laurell, Fredrik
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Thylén, Lars
    Hewlett-Packard Enterprise Laboratories, Palo Alto, USA ; KTH Royal Institute of Technology, Stockholm, Sweden.
    Wosinski, Lech
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Östling, Mikael
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Toprak, Muhammet S.
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Popov, Sergei
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Direct birefringence and transmission modulation via dynamic alignment of P3HT nanofibers in an advanced opto-fluidic component2017Ingår i: Optical Materials Express, ISSN 2159-3930, E-ISSN 2159-3930, Vol. 7, nr 1, 52-61 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Poly-3-hexylthiophene (P3HT) nanofibers are semiconducting high-aspect ratio nanostructures with anisotropic absorption and birefringence properties found at different regions of the optical spectrum. In addition, P3HT nanofibers possess an ability to be aligned by an external electric field, while being dispersed in a liquid. In this manuscript we show that such collective ordering of nanofibers, similar to liquid crystal material, significantly changes the properties of transmitted light. With a specially fabricated opto-fluidic component, we monitored the phase and transmission modulation of light propagating through the solution of P3HT nanofibers, being placed in the electric field with strength up to 0.1 V/μm. This report describes a technique for light modulation, which can be implemented in optical fiber-based devices or on-chip integrated components.

  • 49. Lopez, V
    et al.
    Gran, JM
    Fernandez-Palacios, JP
    Siracusa, D
    Gerstel, O
    Shikhmanter, Y
    Mårtensson, Jonas
    RISE, Swedish ICT, Acreo.
    Sköldström, Pontus
    RISE, Swedish ICT, Acreo.
    Szyrkowiec, T
    Chamania, M
    Autenrieth, A
    Tomkos, Ioannis
    Klonidis, D
    RISE, Swedish ICT, Acreo, Broadband Technology.
    The role of SDN in Application Centric IP and Optical Networks2016Ingår i: European Conference on Networks and Communications (EuCNC), IEEE, 2016Konferensbidrag (Refereegranskat)
    Abstract [en]

    Transport IP/optical networks are evolving in capacity and dynamicity configuration. This evolution gives little to no attention to the specific needs of applications, beyond raw capacity. The ACINO concept is based on facilitating applications to explicitly specify requirements for requested services in terms of high-level (technology agnostic) requirements such as maximum latency or reliability. These requirements are described using intents and certain primitives which facilitate translation to technology specific configuration within the ACINO infrastructure. To support this application centric approach, SDN must have a key role in this evolution. There are representative use cases where SDN gives an added value when considering not only the network but also the application layer.

  • 50.
    Ludwig, Frank
    et al.
    TU Braunschweig, Braunschweig, Germany.
    Balceris, christoph
    TU Braunschweig, Braunschweig, Germany.
    Viereck, Thilo
    TU Braunschweig, Braunschweig, Germany.
    Posth, Oliver
    Physikalisch-Technische Bundesanstalt, Berlin, Germany.
    Steinhoff, Uwe
    Physikalisch-Technische Bundesanstalt, Berlin, Germany.
    Gavilan, Helena
    ICMM/CSIC, Madrid, Spain.
    Costo, Rocio
    ICMM/CSIC, Madrid, Spain.
    Zeng, Lunjie
    Chalmers University of Technology, Göteborg, Sweden.
    Olsson, Eva
    Chalmers University of Technology, Göteborg, Sweden.
    Jonasson, Christian
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Johansson, Christer
    RISE - Research Institutes of Sweden, IKT, Acreo.
    Size analysis of single-core magnetic nanoparticles2017Ingår i: Journal of Magnetism and Magnetic Materials, ISSN 0304-8853, E-ISSN 1873-4766, Vol. 427, 19-24 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Single-core iron-oxide nanoparticles with nominal core diameters of 14 nm and 19 nm were analyzed with a variety of non-magnetic and magnetic analysis techniques, including transmission electron microscopy (TEM), dynamic light scattering (DLS), static magnetization vs. magnetic field (M-H) measurements, ac susceptibility (ACS) and magnetorelaxometry (MRX). From the experimental data, distributions of core and hydrodynamic sizes are derived. Except for TEM where a number-weighted distribution is directly obtained, models have to be applied in order to determine size distributions from the measurand. It was found that the mean core diameters determined from TEM, M-H, ACS and MRX measurements agree well although they are based on different models (Langevin function, Brownian and Néel relaxation times). Especially for the sample with large cores, particle interaction effects come into play, causing agglomerates which were detected in DLS, ACS and MRX measurements. We observed that the number and size of agglomerates can be minimized by sufficiently strong diluting the suspension.

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