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Author Antipov, S.; Trifonov, A.; Krause, S.; Meledin, D.; Desmaris, V.; Belitsky, V.; Gol’tsman, G. openurl 
  Title Gain bandwidth of NbN HEB mixers on GaN buffer layer operating at 2 THz local oscillator frequency Type Conference Article
  Year 2017 Publication Proc. 28th Int. Symp. Space Terahertz Technol. Abbreviated Journal Proc. 28th Int. Symp. Space Terahertz Technol.  
  Volume Issue Pages (up) 147-148  
  Keywords NbN HEB mixers, GaN buffer-layer, IF bandwidth  
  Abstract In this paper, we present IF bandwidth measurement results of NbN HEB mixers, which are employing NbN thin films grown on a GaN buffer-layer. The HEB mixers were operated in the heterodyne regime at a bath temperature of approximately 4.5 K and with a local oscillator operating at a frequency of 2 THz. A quantum cascade laser served as the local oscillator and a reference synthesizer based on a BWO generator (130-160 GHz) and a semiconductor superlattice (SSL) frequency multiplier was used as a signal source. By changing the LO frequency it was possible to record the IF response or gain bandwidth of the HEB with a spectrum analyzer at the operation point, which yielded lowest noise temperature. The gain bandwidth that was recorded in the heterodyne regime at 2 THz amounts to approximately 5 GHz and coincides well with a measurement that has been performed at elevated bath temperatures and lower LO frequency of 140 GHz. These findings strongly support that by using a GaN buffer-layer the phonon escape time of NbN HEBs can be significantly lower as compared to e.g. Si substrate, thus, providing higher gain bandwidth.  
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  Call Number Serial 1175  
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Author Gao, J. R.; Hajenius, M.; Baselmans, J. J. A.; Yang, Z. Q.; Baryshev, A. M.; Barends, R.; Klapwijk, T. M.; Voronov, B.; Gol'tsman, G.; Callaos, N. url  isbn
openurl 
  Title Twin-slot antenna coupled NbN hot electron bolometer mixers for space applications Type Conference Article
  Year 2005 Publication Proc. 9-th WMSCI Abbreviated Journal Proc. 9-th WMSCI  
  Volume 9 Issue Pages (up) 148-153  
  Keywords NbN HEB mixers  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher International Institute of Informatics and Systemics Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN 9806560639, 9789806560635 Medium  
  Area Expedition Conference 9th World Multi-Conference on Systemics, Cybernetics and Informatics  
  Notes Approved no  
  Call Number Serial 1480  
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Author Yagoubov, P.; Kroug, M.; Merkel, H.; Kollberg, E.; Schubert, J.; Hubers, H.-W.; Schwaab, G.; Gol’tsman, G.; Gershenzon, E. url  doi
openurl 
  Title Performance of NbN phonon-cooled hot-electron bolometric mixer at Terahertz frequencies Type Conference Article
  Year 1998 Publication Proc. 6-th Int. Conf. Terahertz Electron. Abbreviated Journal Proc. 6-th Int. Conf. Terahertz Electron.  
  Volume Issue Pages (up) 149-152  
  Keywords NbN HEB mixers  
  Abstract The performance of a NbN based phonon-cooled Hot Electron Bolometric (HEB) quasioptical mixer is investigated in the 0.65-3.12 THz frequency range. The device is made from a 3 nm thick NbN film on high resistivity Si and integrated with a planar spiral antenna on the same substrate. The in-plane dimensions of the bolometer strip are 0.2/spl times/2 /spl mu/m. The results of the DSB noire temperature are: 1300 K at 650 GHz, 4700 K at 2.5 TBz and 10000 K at 3.12 THz. The RF bandwidth of the receiver is at least 2.5 THz. The amount of LO power absorbed in the bolometer is about 100 nW. The mixer is linear to within 1 dB compression up to the signal level 10 dB below that of the LO. The intrinsic single sideband conversion gain is measured to be -9 dB, the total conversion gain -14 dB.  
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  Area Expedition Conference IEEE Sixth International Conference on Terahertz Electronics Proceedings. THZ 98. (Cat. No.98EX171)  
  Notes Approved no  
  Call Number Serial 1582  
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Author Goltsman, Gregory N.; Vachtomin, Yuriy B.; Antipov, Sergey V.; Finkel, Matvey I.; Maslennikov, Sergey N.; Polyakov, Stanislav L.; Svechnikov, Sergey I.; Kaurova, Natalia S.; Grishina, Elisaveta V.; Voronov, Boris M. url  openurl
  Title Low-noise NbN phonon-cooled hot-electron bolometer mixers for terahertz heterodyne receivers Type Conference Article
  Year 2005 Publication Proc. 9-th WMSCI Abbreviated Journal Proc. 9-th WMSCI  
  Volume 9 Issue Pages (up) 154-159  
  Keywords NbN HEB mixers  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher International Institute of Informatics and Systemics Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 547  
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Author Verevkin, A. A.; Pearlman, A.; Slysz, W.; Zhang, J.; Sobolewski, R.; Chulkova, G.; Okunev, O.; Kouminov, P.; Drakinskij, V.; Smirnov, K.; Kaurova, N.; Voronov, B.; Gol’tsman, G.; Currie, M. url  doi
openurl 
  Title Ultrafast superconducting single-photon detectors for infrared wavelength quantum communications Type Conference Article
  Year 2003 Publication Proc. SPIE Abbreviated Journal Proc. SPIE  
  Volume 5105 Issue Pages (up) 160-170  
  Keywords NbN SSPD, SNSPD, applications, single-photon detector, quantum cryptography, quantum communications, superconducting devices  
  Abstract We have developed a new class of superconducting single-photon detectors (SSPDs) for ultrafast counting of infrared (IR) photons for secure quantum communications. The devices are operated on the quantum detection mechanism, based on the photon-induced hotspot formation and subsequent appearance of a transient resistive barrier across an ultrathin and submicron-wide superconducting stripe. The detectors are fabricated from 3.5-nm-thick NbN films and they operate at 4.2 K inside a closed-cycle refrigerator or liquid helium cryostat. Various continuous and pulsed laser sources have been used in our experiments, enabling us to determine the detector experimental quantum efficiency (QE) in the photon-counting mode, response time, time jitter, and dark counts. Our 3.5-nm-thick SSPDs reached QE above 15% for visible light photons and 5% at 1.3 – 1.5 μm infrared range. The measured real-time counting rate was above 2 GHz and was limited by the read-out electronics (intrinsic response time is <30 ps). The measured jitter was <18 ps, and the dark counting rate was <0.01 per second. The measured noise equivalent power (NEP) is 2 x 10-18 W/Hz1/2 at λ = 1.3 μm. In near-infrared range, in terms of the counting rate, jitter, dark counts, and overall sensitivity, the NbN SSPDs significantly outperform their semiconductor counterparts. An ultrafast quantum cryptography communication technology based on SSPDs is proposed and discussed.  
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  Corporate Author Thesis  
  Publisher SPIE Place of Publication Editor Donkor, E.; Pirich, A.R.; Brandt, H.E.  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference Quantum Information and Computation  
  Notes Approved no  
  Call Number Serial 1514  
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Author Verevkin, A. A.; Ptitsina, N. G.; Smirnov, K. V.; Gol'tsman, G. N.; Voronov, B. M.; Gershenzon, E. M.; Yngvesson, K. S. url  openurl
  Title Hot electron bolometer detectors and mixers based on a superconducting-two-dimensional electron gas-superconductor structure Type Conference Article
  Year 1997 Publication Proc. 4-th Int. Semicond. Device Research Symp. Abbreviated Journal Proc. 4-th Int. Semicond. Device Research Symp.  
  Volume Issue Pages (up) 163-166  
  Keywords S-2DEG-S HEB mixers, detectors, AlGaAs/GaAs heterostructures, NbN  
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  Notes Approved no  
  Call Number Serial 1603  
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Author Meledin, D.; Tong, C. Y.-E.; Blundell, R.; Kaurova, N.; Smirnov, K.; Voronov, B.; Gol'tsman, G. doi  openurl
  Title Study of the IF bandwidth of NbN HEB mixers based on crystalline quartz substrate with an MgO buffer layer Type Journal Article
  Year 2003 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.  
  Volume 13 Issue 2 Pages (up) 164-167  
  Keywords NbN HEB mixer  
  Abstract In this paper, we present the results of IF bandwidth measurements on 3-4 nm thick NbN hot electron bolometer waveguide mixers, which have been fabricated on a 200-nm thick MgO buffer layer deposited on a crystalline quartz substrate. The 3-dB IF bandwidth, measured at an LO frequency of 0.81 THz, is 3.7 GHz at the optimal bias point for low noise receiver operation. We have also made measurements of the IF dynamic impedance, which allow us to evaluate the intrinsic electron temperature relaxation time and self-heating parameters at different bias conditions.  
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  Notes Approved no  
  Call Number Serial 341  
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Author Semenov, Alexei D.; Hübers, Heinz-Wilhelm; Richter, Heiko; Smirnov, Konstantin; Gol'tsman, Gregory N.; Voronov, Boris M. url  openurl
  Title Superconducting hot-electron bolometer mixer for terahertz heterodyne receivers Type Abstract
  Year 2004 Publication Proc. 15th Int. Symp. Space Terahertz Technol. Abbreviated Journal Proc. 15th Int. Symp. Space Terahertz Technol.  
  Volume Issue Pages (up) 164  
  Keywords NbN HEB mixers  
  Abstract A number of on-going astronomical and atmospheric research programs are aimed to the Terahertz (THz) spectral region. At frequencies above about 1.4 THz heterodyne receivers planned for these missions will use superconducting hot-electron bolometers as a mixers. We present current results on the development of superconducting NbN hot- electron bolometer mixer and quasioptical radiation coupling scheme for GREAT (German Receiver for Astronomy at Terahertz Frequencies, to be used aboard of SOFIA) and TELIS (Terahertz Limb Sounder). The mixer is incorporated into hybrid antenna consisting of a planar feed antenna, which has either logarithmic spiral or double-slot configuration, and hyperhemispherical silicon lens. For the log-spiral feed antenna, the double side-band receiver noise temperature of 5500 K was achieved at 4.3 THz. The noise temperature shows less than 3 dB increase in the intermediate frequency band from 4 GHz to 7 GHz. The hybrid antenna had almost frequency independent and symmetric radiation pattern with the beam-width slightly broader than expected for a diffraction limited pattern. Results of FTS measurements in the direct detection regime agreed with the spectral dependence of the noise temperature for spiral antennas with different spacing of inner terminals.  
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  Notes Approved no  
  Call Number Serial 1492  
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Author Semenov, A. D.; Hübers, Heinz-Wilhelm; Richter, H.; Birk, M.; Krocka, M.; Mair, U.; Vachtomin, Yu. B.; Finkel, M. I.; Antipov, S. V.; Voronov, B. M.; Smirnov, K. V.; Kaurova, N. S.; Drakinski, V. N.; Gol'tsman, G. N. doi  openurl
  Title Superconducting hot-electron bolometer mixer for terahertz heterodyne receivers Type Journal Article
  Year 2003 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal  
  Volume 13 Issue 2 Pages (up) 168-171  
  Keywords NbN HEB mixers  
  Abstract We present recent results showing the development of superconducting NbN hot-electron bolometer mixer for German receiver for astronomy at terahertz frequencies and terahertz limb sounder. The mixer is incorporated into a planar feed antenna, which has either logarithmic spiral or double-slot configuration, and backed on a silicon lens. The hybrid antenna had almost frequency independent and symmetric radiation pattern slightly broader than expected for a diffraction limited antenna. At 2.5 THz the best 2200 K double side-band receiver noise temperature was achieved across a 1 GHz intermediate frequency bandwidth centred at 1.5 GHz. For this operation regime, a receiver conversion efficiency of -17 dB was directly measured and the loss budget was evaluated. The mixer response was linear at load temperatures smaller than 400 K. Implementation of the MgO buffer layer on Si resulted in an increased 5.2 GHz gain bandwidth. The receiver was tested in the laboratory environment by measuring a methanol emission line at 2.5 THz.  
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  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 343  
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Author Tong, C. Edward; Trifonov, Andrey; Blundell, Raymond; Shurakov, Alexander; Gol’tsman, Gregory url  openurl
  Title A digital terahertz power meter based on an NbN thin film Type Abstract
  Year 2014 Publication Proc. 25th Int. Symp. Space Terahertz Technol. Abbreviated Journal Proc. 25th Int. Symp. Space Terahertz Technol.  
  Volume Issue Pages (up) 170  
  Keywords waveguide NbN HEB mixers  
  Abstract We have further studied the effect of subjecting a superconducting Hot Electron Bolometer (HEB) element made from an NbN thin film to microwave radiation. Since the photon energy is weak, the microwave radiation does not simply heat the film, but generates a bi-static state, switching between the superconducting and normal states, upon the application of a small voltage bias. Indeed, a relaxation oscillation of a few MHz has previously been reported in this regime [1]. Switching between the superconducting and normal states modulates the reflected microwave pump power from the device. A simple homodyne setup readily recovers the spontaneous switching waveform in the time domain. The switching frequency is a function of both the bias voltage (DC heating) and the applied microwave power. In this work, we use a 0.8 THz HEB waveguide mixer for the purpose of demonstration. The applied microwave pump, coupled through a directional coupler, is at 1 GHz. Since the pump power is of the order of a few μW, a room temperature amplifier is sufficient to amplify the reflected pump power from the HEB mixer, which beats with the microwave source in a homodyne set-up. After further amplification, the switching waveform is passed onto a frequency counter. The typical frequency of the switching pulses is 3-5 MHz. It is found that the digital frequency count increases with higher microwave pump power. When the HEB mixer is subjected to additional optical power at 0.8 THz, the frequency count also increases. When we vary the incident optical power by using a wire grid attenuator, a linear relationship is observed between the frequency count and the applied optical power, over at least an order of magnitude of power. This phenomenon can be exploited to develop a digital power meter, using a very simple electronics setup. Further experiments are under way to determine the range of linearity and the accuracy of calibration transfer from the microwave to the THz regime. References 1. Y. Zhuang, and S. Yngvesson, “Detection and interpretation of bistatic effects in NbN HEB devices,” Proc. 13 th Int. Symp. Space THz Tech., 2002, pp. 463–472.  
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  Notes Approved no  
  Call Number Serial 1366  
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Author Semenov, A.; Engel, A.; Il'in, K.; Gol'tsman, G.; Siegel, M.; Hübers, H.-W. url  doi
openurl 
  Title Ultimate performance of a superconducting quantum detector Type Journal Article
  Year 2003 Publication Eur. Phys. J. Appl. Phys. Abbreviated Journal Eur. Phys. J. Appl. Phys.  
  Volume 21 Issue 3 Pages (up) 171-178  
  Keywords NbN SSPD, SNSPD  
  Abstract We analyze the ultimate performance of a superconducting quantum detector in order to meet requirements for applications in near-infrared astronomy and X-ray spectroscopy. The detector exploits a combined detection mechanism, in which avalanche quasiparticle multiplication and the supercurrent jointly produce a voltage response to a single absorbed photon via successive formation of a photon-induced and a current-induced normal hotspot in a narrow superconducting strip. The response time of the detector should increase with the photon energy providing energy resolution. Depending on the superconducting material and operation conditions, the cut-off wavelength for the single-photon detection regime varies from infrared waves to visible light. We simulated the performance of the background-limited infrared direct detector and X-ray photon counter utilizing the above mechanism. Low dark count rate and intrinsic low-frequency cut-off allow for realizing a background limited noise equivalent power of 10−20 W Hz−1/2 for a far-infrared direct detector exposed to 4-K background radiation. At low temperatures, the intrinsic response time of the counter is rather determined by diffusion of nonequilibrium electrons than by the rate of energy transfer to phonons. Therefore, thermal fluctuations do not hamper energy resolution of the X-ray photon counter that should be better than 10−3 for 6-keV photons. Comparison of new data obtained with a Nb based detector and previously reported results on NbN quantum detectors support our estimates of ultimate detector performance.  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1286-0042 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 534  
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Author Maslennikov, S. N.; Finkel, M. I.; Antipov, S. V.; Polyakov, S. L.; Zhang, W.; Ozhegov, R.; Vachtomin, Yu. B.; Svechnikov, S. I.; Smirnov, K. V.; Korotetskaya, Yu. P.; Kaurova, N. S.; Gol'tsman, G. N.; Voronov, B. M. url  openurl
  Title Spiral antenna coupled and directly coupled NbN HEB mixers in the frequency range from 1 to 70 THz Type Conference Article
  Year 2006 Publication Proc. 17th Int. Symp. Space Terahertz Technol. Abbreviated Journal Proc. 17th Int. Symp. Space Terahertz Technol.  
  Volume Issue Pages (up) 177-179  
  Keywords directly coupled NbN HEB mixers  
  Abstract We investigate both antenna coupled and directly coupled HEB mixers at several LO frequencies within the range of 2.5 THz to 70 THz. H20 (2.5+10.7 THz), and CO2 (30 THz) gas discharge lasers are used as the local oscillators. The noise temperature of antenna coupled mixers is measured at LO frequencies of 2.5 THz, 3.8 THz, and 30 THz. The results for both antenna coupled and directly coupled mixer types are compared. The devices with in—plane dimensions of 5x5 ,um 2 are pumped by LO radiation at 10.7 THz. The directly coupled HEB demonstrates nearly flat dependence of responsivity on frequency in the range of 25+64 THz.  
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  Publisher Place of Publication Paris, France Editor  
  Language Summary Language Original Title  
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  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 386  
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Author Gol’tsman, G. N.; Gershenzon, E. M. url  doi
openurl 
  Title High speed hot-electron superconducting bolometer Type Conference Article
  Year 1993 Publication Proc. SPIE Abbreviated Journal Proc. SPIE  
  Volume 2104 Issue Pages (up) 181-182  
  Keywords NbN HEb, Nb, Al  
  Abstract Physical limitation of response time of a superconducting bolometer as well as the nature of non-equilibrium detection of radiation have been investigated for Al, Nb and NbN thin films in spectral range from submillimeter to near-infraredwavelengths [1,2]. In the case of ideal heat removal from the film with the f_‘. 100A thickness the detection mechanism is an electron heating effect that is not selective to radiation wavelength in a very broad range. The response time ofan electron heating bolometer is determined by an electron-phonon interaction time. This time is of about 10 ns, 0.5 ns and 20 ps for Al, Nb, and NbN correspondingly near the critical temperature of the superconducting film. Thesensitive area of the bolometer consists of a number of narrow strips (with awidth of 1µm) connected in parallel to contact pads; these pads together witha sapphire substrate and a ground plate represent the microstrip transmissionline with an impedance of 50 Q.  
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  Corporate Author Thesis  
  Publisher SPIE Place of Publication Editor Birch, J.R.; Parker, T.J.  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference 18th International Conference on Infrared and Millimeter Waves  
  Notes Approved no  
  Call Number Serial 1652  
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Author Semenov, A.; Richter, H.; Smirnov, A.; Günther, B.; Hübers, H.-W.; Il’in, K.; Siegel, M.; Gol’tsman, G.; Drakinskiy, V.; Merkel, H.; Karamarkovic, J. url  openurl
  Title Development of HEB mixers for GREAT and for security screening Type Abstract
  Year 2007 Publication Proc. 18th Int. Symp. Space Terahertz Technol. Abbreviated Journal Proc. 18th Int. Symp. Space Terahertz Technol.  
  Volume Issue Pages (up) 184  
  Keywords NbN HEB mixers, GREAT  
  Abstract We report the study on the quasioptical coupling efficiency and the gain bandwidth of NbN hot-electron bolometer mixers developed for the 4.7 THz channel of the German receiver for Astronomy at THz-frequencies (GREAT) and for security screening at subterahertz frequencies. Radiation coupling efficiency and directive properties of integrated lens antennas with log-spiral, log-periodic and double-slot planar feeds coupled to a hot-electron bolometer were experimentally studied at frequencies from 1 THz to 6 THz and compared with simulations based on the method of moments and the physical-optics ray tracing. For all studied antennas the modeled spectral dependence of the coupling efficiency fits to the experimental data obtained with both Fourier transform spectroscopy and noise temperature measurements only if the complex impedance of the bolometer is explicitly taken into account. Our experimental data did not indicate any noticeable contribution of the quantum noise to the system noise temperature. The experimentally observed deviation of the beam pattern from the model prediction increases with frequency and is most likely due to a non- ideality of the presently used lenses. Study of the intermediate frequency mixer gain at local oscillator (LO) frequencies between 2.5 THz and 0.3 THz showed an increase of the gain bandwidth at low LO frequencies that was understood as the contribution of the direct interaction of magnetic vortices with the radiation field. We have found that the non- homogeneous hot-spot model more adequately describes variation of the intermediate frequency bandwidth with the applied local oscillator power than any of uniform mixer models. The state-of-the-day performance of the GREAT 4.7-THz channel and the 0.8-THz security scanner will be presented.  
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  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 1420  
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Author Gao, J. R.; Hajenius, M.; Tichelaar, F. D.; Voronov, B.; Grishina, E.; Klapwijk, T. M.; Gol'tsman, G.; Zorman, C. A. url  openurl
  Title Can NbN films on 3C-SiC/Si change the IF bandwidth of hot electron bolometer mixers? Type Conference Article
  Year 2006 Publication Proc. 17th Int. Symp. Space Terahertz Technol. Abbreviated Journal Proc. 17th Int. Symp. Space Terahertz Technol.  
  Volume Issue Pages (up) 187-189  
  Keywords NbN HEB mixers  
  Abstract We realized ultra thin NbN films sputtered grown on a 3C-SiC/Si substrate. The film with a thickness of 3.5-4.5 nm shows a 1', of 11.8 K, which is the highest I`, observed among ultra thin NbN films on different substrates. The high-resolution transmission electron microscopy (HRTEM) studies show that the film has a monocrystalline structure, confirming the epitaxial growth on the 3C-SiC. Based on a two-temperature model and input parameters from standard NbN films on Si, simulations predict that the new film can increase the IF bandwidth of a HEB mixer by about a factor of 2 in comparison to the standard films. In addition, we find standard NbN films on Si with a T c of 9.4 K have a thickness of around 5.5 nm, being thicker than expected (3.5 nm).  
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  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 1439  
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