Searched for: subject:"superconductor"
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Liu, D. (author), Polinder, H. (author), Abrahamsen, Asger Bech (author), Ferreira, J.A. (author)
This paper aims at assessing the potential of partially superconducting generators for 10 MW direct-drive wind turbines by investigating their performance for a very wide range of excitation currents. Performance indicators such as shear stress and efficiency and other generator characteristics are compared for 12 different generator topologies....
journal article 2017
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Shcherbatenko, M (author), Tretyakov, I (author), Lobanov, Yu (author), Maslennikov, S. N. (author), Kaurova, N (author), Finkel, M. (author), Voronov, B (author), Goltsman, G (author), Klapwijk, T.M. (author)

We present a physically consistent interpretation of the dc electrical properties of niobiumnitride (NbN)-based superconducting hot-electron bolometer mixers, using concepts of nonequilibrium superconductivity. Through this, we clarify what physical information can be extracted from the resistive transition and the dc current-voltage...

journal article 2016
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Vuik, A. (author), Eeltink, D. (author), Akhmerov, A.R. (author), Wimmer, M.T. (author)
One of the promising platforms for creating Majorana bound states is a hybrid nanostructure consisting of a semiconducting nanowire covered by a superconductor.Weanalyze the previously disregarded role of electrostatic interaction in these devices. Our main result is that Coulomb interaction causes the chemical potential to respond to an applied...
journal article 2016
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Zuo, K. (author), Mourik, V. (author)
Majorana fermions are exotic elementary particles predicted in 1937 by Ettore Majorana. Although heavily searched for, they have never been found in nature up to date. In the past decades, with the progress in theory, theoretical physicists predicted that Majorana fermions might emerge in certain exotic classes of condensed matter systems, where...
doctoral thesis 2016
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Godschalk, F. (author)
In this dissertation, we study a novel class of laser devices, referred to as half-Josephson lasers (HJL). Here, lasing at half the Josephson frequency is induced by a parametric instability, resulting from an oscillating supercurrent flowing through a Josephson junction that contains quantum emitters. The device combines the electronic...
doctoral thesis 2014
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Smit, J.J. (author), Andritsch, T. (author), Chevtchenko, O.A. (author)
Assets in high voltage technology have to meet harsh service conditions over long lifetimes of 40 years or more. Due to environmental concerns, substitution of conventional insulating materials becomes a necessity. Because robustness and sustainability are serious requirements, only few new materials are really breaking through. At present some...
journal article 2012
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Etaki, S. (author)
Mechanical sensors are essential tools for the detection of small forces. This thesis presents the dc SQUID as a detector for the displacement of embedded micromechanical resonators. The device geometry and basic operating principle are described. The SQUID displacement detector reaches an excellent resolution, a factor of 1.5 below the standard...
doctoral thesis 2012
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Rashid, M. (author)
The electromagnetic waves are considered in this article as the mediators of interaction in the Meissner Effect or the diamagnetic property of the superconductors. During the cooling of a superconductor electromagnetic waves may be released when the electrons occupy lower states of the energy. These electromagnetic waves may combine in...
journal article 2011
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Vercruyssen, N. (author), Barends, R. (author), Klapwijk, T.M. (author), Muhonen, J.T. (author), Meschke, M. (author), Pekola, J.P. (author)
We demonstrate an increased quasiparticle recombination time in superconducting resonators on a SiNx membrane, compared to identical resonators on a SiNx/Si wafer. An interpretation is given using a thermal model of the membrane. Using an array of tunnel junctions to cool or heat the membrane, we show that the resonators on the membranes are...
journal article 2011
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Marsili, F. (author), Najafi, F. (author), Herder, C. (author), Berggren, K.K. (author)
We developed an electrothermal model of NbN superconducting nanowire avalanche photodetectors (SNAPs) on sapphire substrates. SNAPs are single-photon detectors consisting of the parallel connection of N superconducting nanowires. We extrapolated the physical constants of the model from experimental data and we simulated the time evolution of the...
journal article 2011
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Khudchenko, A. (author), Zijlstra, T. (author), Klapwijk, T. et al (author)
The ALMA Band 9 receiver cartridge (600-720 GHz) based on Dual Sideband (DSB) superconductor-insulatorsuperconductor (SIS) mixer is currently in full production. In the case of spectral line observations, the integration time to reach a certain signal-to-noise level can be reduced by about a factor of two by rejecting an unused sideband. The...
conference paper 2010
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Mauskopf, P. (author), Morozov, D. (author), Glowacka, D. (author), Goldie, D. (author), Withington, S. (author), Bruijn, M. (author), De Korte, P. (author), Hoevers, H. (author), Ridder, M. (author), Van der Kuur, J. (author), Gao, J.R. (author)
We describe the optimization of transition edge superconducting (TES) detectors for use in a far-infrared (FIR) Fourier transform spectrometer (FTS) mounted on a cryogenically cooled space-borne telescope (e.g. SPICA). The required noise equivalent power (NEP) of the detectors is approximately 10?19 W/ ?Hz in order to be lower than the photon...
conference paper 2008
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Barends, R. (author), Hortensius, H.L. (author), Zijlstra, T. (author), Baselmans, J.J.A. (author), Yates, S.J.C. (author), Gao, J.R. (author), Klapwijk, T.M. (author)
We study NbTiN resonators by measurements of the temperature dependent resonance frequency and frequency noise. Additionally, resonators are studied covered with SiOx dielectric layers of various thicknesses. The resonance frequency develops a nonmonotonic temperature dependence with increasing SiOx layer thickness. The increase in the noise is...
journal article 2008
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Mohammadkhani, G. (author), Zareyan, M. (author), Blanter, Y.M. (author)
journal article 2008
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Khosropanah, P. (author), Gao, J.R. (author), Laauwen, W.M. (author), Hajenius, M. (author), Klapwijk, T.M. (author)
We have studied the sensitivity of a superconducting NbN hot electron bolometer mixer integrated with a spiral antenna at 4.3?THz. Using hot/cold blackbody loads and a beam splitter all in vacuum, we measured a double sideband receiver noise temperature of 1300?K at the optimum local oscillator (LO) power of 330?nW, which is about 12 times the...
journal article 2007
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Man, H.T. (author)
Carbon Nanotubes are molecules with exceptional physical properties that are most useful for applications in the growing field of nanotechnology. In addition, because of its special electrical properties, they are extremely useful for experiments on the fundamental properties of one-dimensional electronic systems. This thesis describes a series...
doctoral thesis 2006
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Jackson, B.D. (author), De Lange, G. (author), Zijlstra, T. (author), Kroug, M. (author), Klapwijk, T.M. (author), Stern, J.A. (author)
Integrating NbTiN-based microstrip tuning circuits with traditional Nb superconductor-insulator-superconductor (SIS) junctions enables the low-noise operation regime of SIS mixers to be extended from below 0.7?to?1.15?THz. In particular, mixers incorporating a NbTiN/SiO2/NbTiN microstrip tuning circuit offer low-noise performance below 0.8–0.85...
journal article 2005
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Baselmans, J.J.A. (author), Hajenius, M. (author), Gao, J.R. (author), Klapwijk, T.M. (author), De Korte, P.A.J. (author), Voronov, B. (author), Gol'tsman, G. (author)
We demonstrate that the performance of NbN lattice cooled hot electron bolometer mixers depends strongly on the interface quality between the bolometer and the contact structure. We show experimentally that both the receiver noise temperature and the gain bandwidth can be improved by more than a factor of 2 by cleaning the interface and adding...
journal article 2004
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Pedarnig, J.D. (author), Rössler, R. (author), Delamare, M.P. (author), Lang, W. (author), Bäuerle, D. (author), Köhler, A. (author), Zandbergen, H.W. (author)
Vicinal YBa2Cu3O7?? (YBCO) thin films of thickness h = 20–480?nm are grown by pulsed-laser deposition on 10° miscut (001) SrTiO3 substrates. The anisotropic resistivities, c-axis texture, and critical temperature drastically depend on the thickness of vicinal films. High-resolution electron microscopy reveals a defect microstructure with strong...
journal article 2002
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Jak, M.J.G. (author), Riess, I. (author), Schoonman, J. (author), Chowdari, B.V.R. (author)
journal article 1996
Searched for: subject:"superconductor"
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