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Author Darula, Marian; Semenov, Alex D.; Hübers, Heinz-Wilhelm; Schubert, Josef url  openurl
  Title Quasioptical high-Tc superconductor Josephson mixer at terahertz frequencies Type Abstract
  Year 2000 Publication Proc. 11th Int. Symp. Space Terahertz Technol. Abbreviated Journal (up) Proc. 11th Int. Symp. Space Terahertz Technol.  
  Volume Issue Pages 515  
  Keywords HTS Josephson mixers  
  Abstract Mixers based on Josephson junctions from conventional superconductor materials have demonstrated excellent performance at subgap frequencies. The advantages of Josephson mixers are low optimal power of the local oscillator and large intermediate frequency bandwidth but their noise temperature increases dramatically at frequencies corresponding to the energy gap of the superconductor, which is typically below 1 THz for widely used materials. The large energy gap of oxide superconductors makes them promising candidates for development of terahertz Josephson mixers. Here we report on experimental study of the quasioptical mixer utilizing bicrystal Josephson junction from high-transition-temperature YBa 2 Cu 3 O 7-δ film. Junctions with a width of 2 µm were fabricated from 100 nm thick laser ablated films on bicrystal MgO substrates and had the and the J C R n product of about 2 mV at 4.2 K. The planar complementary logarithmic spiral antenna incorporated into co-planar waveguide was patterned from 200 nm thick gold film thermally evaporated in situ on top of the YBa 2 Cu 3 O 7-δ film. The mixer chip was clamped to the extended hemispherical silicon lens. Performance of the mixer was investigated at 4.5 K bath temperature. We used FIR laser as a local oscillator at frequencies 0.698 and 2.52 THz. System noise temperature (DSB) was determined from Y-factor measured with 300 K and 77 K loads. At 0.698 THz the lowest noise temperature 1750 K was observed when the mixer was biased with the fixed current to the region in the vicinity of either the first Shapiro step or the critical current. Between these two bias points the noise temperature increased to ≈ 20000 K. As function of the local oscillator power the noise temperature reached the minimum when the critical current was suppressed to the half of its equilibrium value. Power of the local oscillator absorbed by the mixer at optimal operation was of the order 100 nW. The present design of our antenna limits the upper operation frequency to the value of 1.8 THz. Nevertheless, we clearly observed Shapiro steps at the frequency 2.52 THz. Bearing in mind an improved design of the antenna, we estimate the 3000 K DSB noise temperature at this frequency.  
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  Call Number Serial 1555  
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Author Cherednichenko, S.; Rönnung, F.; Gol’tsman, G.; Kollberg, E.; Winkler, D. url  openurl
  Title YBa2Cu3O7-δ hot-electron bolometer mixer at 0.6 THz Type Conference Article
  Year 2000 Publication Proc. 11th Int. Symp. Space Terahertz Technol. Abbreviated Journal (up) Proc. 11th Int. Symp. Space Terahertz Technol.  
  Volume Issue Pages 517-522  
  Keywords YBCO HTS HEB mixers  
  Abstract We present an investigation of hot-electron bolometric mixer based on a YBa 2 Cu 3 O 7-δ (YBCO) superconducting thin film. Mixer conversion loss of –46 dB, absorbed local oscillator power and intermediate frequency bandwidth were measured at the local oscillator frequency 0.6 THz. The fabrication technique for nanoscale YBCO hot-electron bolometer (HEB) mixer integrated with a planar antenna structure is described.  
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  Notes Approved no  
  Call Number Serial 1556  
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Author Cherednichenko, S.; Kroug, M.; Yagoubov, P.; Merkel, H.; Kollberg, E.; Yngvesson, K. S.; Voronov, B.; Gol’tsman, G. url  openurl
  Title IF bandwidth of phonon cooled HEB mixers made from NbN films on MgO substrates Type Conference Article
  Year 2000 Publication Proc. 11th Int. Symp. Space Terahertz Technol. Abbreviated Journal (up) Proc. 11th Int. Symp. Space Terahertz Technol.  
  Volume Issue Pages 219-227  
  Keywords NbN HEB mixers, cinversion gain bandwidth, IF bandwidth  
  Abstract An investigation of gain and noise bandwidth of phonon-cooled hot-electron bolometric (HEB) mixers is presented. The radiation coupling to the mixers is quasioptical through either a spiral or twin-slot antenna. A maximum gain bandwidth of 4.8 GHz is obtained for mixers based on a 3.5 nm thin NbN film with Tc= 10 K. The noise bandwidth is 5.6 GHz, at the moment limited by parasitic elements in the, device mount fixture. At 0.65 THz the DSB receiver noise temperature is 700-800 К in the IF band 1-2 GHz, and 1150-2700 К in the band 3.5-7 GHz.  
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  Notes Approved no  
  Call Number Serial 1557  
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Author Cherednichenko, S.; Kroug, M.; Merkel, H.; Kollberg, E.; Loudkov, D.; Smirnov, K.; Voronov, B.; Gol'tsman, G.; Gershenzon, E. url  openurl
  Title Local oscillator power requirement and saturation effects in NbN HEB mixers Type Conference Article
  Year 2001 Publication Proc. 12th Int. Symp. Space Terahertz Technol. Abbreviated Journal (up) Proc. 12th Int. Symp. Space Terahertz Technol.  
  Volume Issue Pages 273-285  
  Keywords NbN HEB mixers, LO power, local oscillator power, saturation effect, dynamic range  
  Abstract The local oscillator power required for NbN hot-electron bolometric mixers (P LO ) was investigated with respect to mixer size, critical temperature and ambient temperature. P LO can be decreased by a factor of 10 as the mixer size decreases from 4×0.4 µm 2 to 0.6×0.13 µm 2 . For the smallest volume mixer the optimal local oscillator power was found to be 15 nW. We found that for such mixer no signal compression was observed up to an input signal of 2 nW which corresponds to an equivalent input load of 20,000 K. For a constant mixer volume, reduction of T c can decrease optimal local oscillator power at least by a factor of 2 without a deterioration of the receiver noise temperature. Bath temperature was found to have minor effect on the receiver characteristics.  
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  Publisher Place of Publication San Diego, CA, USA Editor Jet Propulsion Laboratory, California Inst.it.u.t.e of Technology  
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  Notes Approved no  
  Call Number Serial 318  
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Author Hübers, H.-W.; Semenov, A. D.; Richter, H.; Schubert, J.; Hadjiloucas, S.; Bowen, J. W.; Gol'tsman, G.; Voronov, B. M.; Gershenzon, E. M. url  openurl
  Title Antenna pattern of the quasi-optical hot-electron bolometric mixer at terahertz frequencies Type Conference Article
  Year 2001 Publication Proc. 12th Int. Symp. Space Terahertz Technol. Abbreviated Journal (up) Proc. 12th Int. Symp. Space Terahertz Technol.  
  Volume Issue Pages 286-296  
  Keywords NbN HEB mixers  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication San Diego, CA, USA Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
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  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 323  
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Author Verevkin, A.; Xu, Y.; Zheng, X.; Williams, C.; Sobolewski, Roman; Okunev, O.; Smirnov, K.; Chulkova, G.; Korneev, A.; Lipatov, A.; Gol’tsman, G. N. url  openurl
  Title Superconducting NbN-based ultrafast hot-electron single-photon detector for infrared range Type Conference Article
  Year 2001 Publication Proc. 12th Int. Symp. Space Terahertz Technol. Abbreviated Journal (up) Proc. 12th Int. Symp. Space Terahertz Technol.  
  Volume Issue Pages 462-468  
  Keywords NbN SSPD, SNSPD  
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  Notes Approved no  
  Call Number Serial 1539  
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Author Gol'tsman, Gregory; Semenov, Alexei; Smirnov, Konstantin; Voronov, Boris url  openurl
  Title Background limited quantum superconducting detector for submillimeter wavelengths Type Conference Article
  Year 2001 Publication Proc. 12th Int. Symp. Space Terahertz Technol. Abbreviated Journal (up) Proc. 12th Int. Symp. Space Terahertz Technol.  
  Volume Issue Pages 469-475  
  Keywords Ti SQD, SQUID readout  
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  Notes Approved no  
  Call Number Serial 1540  
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Author Vahtomin, Yuriy B.; Finkel, Matvey I.; Antipov, Sergey V.; Voronov, Boris M.; Smirnov, Konstantin V.; Kaurova, Natalia S.; Drakinski, Vladimir N.; Gol'tsman, Gregogy N. url  openurl
  Title Gain bandwidth of phonon-cooled HEB mixer made of NbN thin film with MgO buffer layer on Si Type Conference Article
  Year 2002 Publication Proc. 13th Int. Symp. Space Terahertz Technol. Abbreviated Journal (up) Proc. 13th Int. Symp. Space Terahertz Technol.  
  Volume Issue Pages 259-270  
  Keywords NbN HEB mixers, conversion gain bandwidth  
  Abstract We present recently obtained values for gain bandwidth of NbN HEB mixers for different substrates and film thicknesses and for MgO buffer layer on Si at LO frequency of 0.85-1 THz. The maximal bandwidth, 5.2 GHz, was achieved for the device on MgO buffer layer on Si with a 2 nm thick NbN film. Functional devices based on NbN films of such thickness were fabricated for the first time due to an improvement of superconducting properties of NbN film deposited on MgO buffer layer on Si substrate.  
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  Publisher Place of Publication Cambridge, MA, USA Editor Harvard university  
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  Notes Approved no  
  Call Number Serial 325  
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Author Meledin, D.; Tong, C. Y.-E.; Blundell, R.; Kaurova, N.; Smirnov, K.; Voronov, B.; Gol'tsman, G. url  openurl
  Title The sensitivity and IF bandwidth of waveguide NbN hot electron bolometer mixers on MgO buffer layers over crystalline quartz Type Conference Article
  Year 2002 Publication Proc. 13th Int. Symp. Space Terahertz Technol. Abbreviated Journal (up) Proc. 13th Int. Symp. Space Terahertz Technol.  
  Volume Issue Pages 65-72  
  Keywords waveguide NbN HEB mixers  
  Abstract We have developed and characterized waveguide phonon-cooled NbN Hot Electron Bolometer (FMB) mixers fabricated from a 3-4 nm thick NbN film deposited on a 200nm thick MgO buffer layer over crystalline quartz. Double side band receiver noise temperatures of 900-1050 K at 1.035 THz, and 1300-1400 K at 1.26 THz have been measured at an intermediate frequency of 1.5 GHz. The intermediate frequency bandwidth, measured at 0.8 THz LO frequency, is 3.2 GHz at the optimal bias point for low noise receiver operation.  
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  Publisher Place of Publication Cambridge, MA, USA Editor Harvard university  
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  Notes Approved no  
  Call Number Serial 326  
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Author Cherednichenko, S.; Kroug, M.; Khosropanah, P.; Adam, A.; Merkel, H.; Kolberg, E.; Loudkov, D.; Voronov, B.; Gol'tsman, G.; Richter, H.; Hübers, H. W. url  openurl
  Title A broadband terahertz heterodyne receiver with an NbN HEB mixer Type Conference Article
  Year 2002 Publication Proc. 13th Int. Symp. Space Terahertz Technol. Abbreviated Journal (up) Proc. 13th Int. Symp. Space Terahertz Technol.  
  Volume Issue Pages 85-95  
  Keywords NbN HEB mixers  
  Abstract We present a broadband and low noise heterodyne receiver for 1.4-1.7 THz designed for the Hershel Space Observatory. A phonon- cooled NbN HEB mixer was integrated with a normal metal double- slot antenna and an elliptical silicon lens. DSB receiver noise temperature Tr was measured from 1 GHz through 8GHz intermediate frequency band with 50 MHz instantaneous bandwidth. At 4.2 K bath temperature and at 1.6 THz LO frequency Tr is 800 K with the receiver noise bandwidth of 5 GHz. While at 2 K bath temperature Tr was as low as 700 K. At 0.6 THz and 1.1 THz a spiral antenna integrated NbN HEB mixer showed the receiver noise temperature 500 K and 800 K, though no antireflection coating was used in this case. Tr of 1100 K was achieved at 2.5 THz while the receiver noise bandwidth was 4 GHz.  
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  Publisher Place of Publication Cambridge, MA, USA Editor Harward University  
  Language Summary Language Original Title  
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  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 332  
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