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Author Svechnikov, S. I.; Okunev, O. V.; Yagoubov, P. A.; Gol'tsman, G. N.; Voronov, B. M.; Cherednichenko, S. I.; Gershenzon, E. M.; Gerecht, E.; Musante, C. F.; Wang, Z.; Yngvesson, K. S. url  doi
openurl 
  Title 2.5 THz NbN hot electron mixer with integrated tapered slot antenna Type Journal Article
  Year 1997 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.  
  Volume 7 Issue 2 Pages 3548-3551  
  Keywords NbN HEB mixers  
  Abstract A Hot Electron Bolometer (HEB) mixer for 2.5 THz utilizing a NbN thin film device, integrated with a Broken Linearly Tapered Slot Antenna (BLTSA), has been fabricated and is presently being tested. The NbN HEB device and the antenna were fabricated on a SiO2membrane. A 0.5 micrometer thick SiO2layer was grown by rf magnetron reactive sputtering on a GaAs wafer. The HEB device (phonon-cooled type) was produced as several parallel strips, 1 micrometer wide, from an ultrathin NbN film 4-7 nm thick, that was deposited onto the SiO2layer by dc magnetron reactive sputtering. The BLTSA was photoetched in a multilayer Ti-Au metallization. In order to strengthen the membrane, the front-side of the wafer was coated with a 5 micrometer thick polyimide layer just before the membrane formation. The last operation was anisotropic etching of the GaAs in a mixture of HNO3and H2O2.  
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  Corporate Author Thesis  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1051-8223 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 1595  
Permanent link to this record
 
 
Author Svechnikov, S.; Gol'tsman, G.; Voronov, B.; Yagoubov, P.; Cherednichenko, S.; Gershenzon, E.; Belitsky, V.; Ekstrom, H.; Kollberg, E.; Semenov, A.; Gousev, Y.; Renk, K. url  doi
openurl 
  Title Spiral antenna NbN hot-electron bolometer mixer at submm frequencies Type Journal Article
  Year 1997 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.  
  Volume 7 Issue 2 Pages 3395-3398  
  Keywords NbN HEB mixers  
  Abstract We have studied the phonon-cooled hot-electron bolometer (HEB) as a quasioptical mixer based on a spiral antenna designed for the 0.3-1 THz frequency band and fabricated on sapphire and high resistivity silicon substrates. HEB devices were produced from superconducting 3.5-5 nm thick NbN films with a critical temperature 10-12 K and a critical current density of approximately 10/sup 7/ A/cm/sup 2/ at 4.2 K. For these devices we reached a DSB receiver noise temperature below 1500 K, a total conversion loss of L/sub t/=16 dB in the 500-700 GHz frequency range, an IF bandwidth of 3-4 GHz and an optimal LO absorbed power of /spl sime/4 /spl mu/W. We experimentally analyzed various contributions to the conversion loss and obtained an RF coupling factor of about 5 dB, internal mixer loss of 10 dB and IF mismatch of 1 dB.  
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  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1051-8223 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 1597  
Permanent link to this record
 
 
Author Ryabchun, S.; Tong, C.-Y. E.; Blundell, R.; Kimberk, R.; Gol'tsman, G. url  doi
openurl 
  Title Study of the effect of microwave radiation on the operation of HEB mixers in the terahertz frequency range Type Journal Article
  Year 2007 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.  
  Volume 17 Issue 2 Pages 391-394  
  Keywords NbN HEB mixers  
  Abstract We have investigated the effect of injecting microwave radiation, with a frequency much lower than that corresponding to the energy gap of the superconductor, on the performance of the hot-electron bolometer mixer incorporated into a THz heterodyne receiver. More specifically, we show that exposing the mixer to microwave radiation does not cause a significant rise of the receiver noise temperature and fall of the mixer conversion gain so long as the microwave power is a small fraction of local oscillator power. The injection of a small, but controlled amount of microwave power therefore enables active compensation of local oscillator power and coupling fluctuations which can significantly degrade the gain stability of hot electron bolometer mixer receivers.  
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  Corporate Author Thesis  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1051-8223 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 1427  
Permanent link to this record
 
 
Author Hajenius, M.; Yang, Z. Q.; Gao, J. R.; Baselmans, J. J. A.; Klapwijk, T. M.; Voronov, B.; Gol'tsman, G. url  doi
openurl 
  Title Optimized sensitivity of NbN hot electron bolometer mixers by annealing Type Journal Article
  Year 2007 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.  
  Volume 17 Issue 2 Pages 399-402  
  Keywords NbN HEB mixers  
  Abstract We report that the heterodyne sensitivity of superconducting hot-electron bolometers (HEBs) increases by 25-30% after annealing at 85degC in high vacuum. The devices studied are twin-slot antenna coupled mixers with a small area NbN bridge of 1 mum times 0.15 mum, above which there is a SiO 2 passivation layer. The mixer noise temperature, gain, and resistance versus temperature curve of a HEB before and after annealing are compared and analysed. We show that the annealing reduces the intrinsic noise of the mixer by 37% and makes the superconducting transition of the bridge and the contacts sharper. We argue that the reduction ofthe noise is mainly due to the improvement of the transparency of the contact/film interface. The lowest receiver noise temperature of 700 K is measured at a local oscillator frequency of 1.63 THz and at a bath temperature of 4.2 K.  
  Address  
  Corporate Author Thesis  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1051-8223 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 1426  
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Author Gol'tsman, G. N.; Karasik, B. S.; Okunev, O. V.; Dzardanov, A. L.; Gershenzon, E. M.; Ekstrom, H.; Jacobsson, S.; Kollberg, E. url  doi
openurl 
  Title NbN hot electron superconducting mixers for 100 GHz operation Type Journal Article
  Year 1995 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.  
  Volume 5 Issue 2 Pages 3065-3068  
  Keywords NbN HEB mixers  
  Abstract NbN is a promising superconducting material for hot-electron superconducting mixers with an IF bandwidth larger than 1 GHz. In the 1OO GHz frequency range, the following parameters were obtained for 50 /spl Aring/ thick NbN films at 4.2 K: receiver noise temperature (DSB) /spl sim/1000 K; conversion loss /spl sim/10 dB; IF bandwidth /spl sim/1 GHz; and local oscillator power /spl sim/1 /spl mu/W. An increase of the critical current of the NbN film, increased working temperature, and a better mixer matching may allow a broader IF bandwidth up to 2 GHz, reduced conversion losses down to 3-5 dB and a receiver noise temperature (DSB) down to 200-300 K.  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1051-8223 ISBN Medium  
  Area Expedition Conference  
  Notes About LO power required Approved no  
  Call Number Serial 255  
Permanent link to this record
 
 
Author Karasik, B. S.; Gol'tsman, G. N.; Voronov, B. M.; Svechnikov, S. I.; Gershenzon, E. M.; Ekstrom, H.; Jacobsson, S.; Kollberg, E.; Yngvesson, K. S. url  doi
openurl 
  Title Hot electron quasioptical NbN superconducting mixer Type Journal Article
  Year 1995 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.  
  Volume 5 Issue 2 Pages 2232-2235  
  Keywords NbN HEB mixers  
  Abstract Hot electron superconductor mixer devices made of thin NbN films on SiO/sub 2/-Si/sub 3/N/sub 4/-Si membrane have been fabricated for 300-350 GHz operation. The device consists of 5-10 parallel strips each 5 /spl mu/m long by 1 /spl mu/m wide which are coupled to a tapered slot-line antenna. The I-V characteristics and position of optimum bias point were studied in the temperature range 4.5-8 K. The performance of the mixer at higher temperatures is closer to that predicted by theory for uniform electron heating. The intermediate frequency bandwidth versus bias has also been investigated. At the operating temperature 4.2 K a bandwidth as wide as 0.8 GHz has been measured for a mixer made of 6 nm thick film. The bandwidth tends to increase with operating temperature. The performance of the NbN mixer is expected to be better for higher frequencies where the absorption of radiation should be more uniform.  
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  Corporate Author Thesis  
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  Series Editor Series Title Abbreviated Series Title  
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  ISSN 1051-8223 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 1622  
Permanent link to this record
 
 
Author Jiang, Ling; Miao, Wei; Zhang, Wen; Li, Ning; Lin, Zhen Hui; Yao, Qi Jun; Shi, Sheng-Cai; Svechnikov, S. I.; Vakhtomin, Y. B.; Antipov, S. V.; Voronov, B. M.; Kaurova, N. S.; Gol'tsman, G. N. url  doi
openurl 
  Title Characterization of a quasi-optical NbN superconducting HEB mixer Type Journal Article
  Year 2006 Publication IEEE Trans. Microwave Theory Techn. Abbreviated Journal IEEE Trans. Microwave Theory Techn.  
  Volume 54 Issue 7 Pages 2944-2948  
  Keywords NbN HEB mixers  
  Abstract In this paper, the performance of a quasi-optical NbN superconducting hot-electron bolometer (HEB) mixer, cryogenically cooled by a close-cycled 4-K refrigerator, is thoroughly investigated at 300, 500, and 850 GHz. The lowest receiver noise temperatures measured at the respective three frequencies are 1400, 900, and 1350 K, which can go down to 659, 413, and 529 K, respectively, after correcting the loss and associated noise contribution of the quasi-optical system before the measured superconducting HEB mixer. The stability of the quasi-optical superconducting HEB mixer is also investigated here. The Allan variance time measured with a local oscillator pumping at 500 GHz and an IF bandwidth of 110 MHz is 1.5 s at the dc-bias voltage exhibiting the lowest noise temperature and increases to 2.5 s at a dc bias twice that voltage.  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0018-9480 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 1448  
Permanent link to this record
 
 
Author Meledin, D. V.; Marrone, D. P.; Tong, C.-Y. E.; Gibson, H.; Blundell, R.; Paine, S. N.; Papa, D.C.; Smith, M.; Hunter, T. R.; Battat, J.; Voronov, B.; Gol'tsman, G. url  doi
openurl 
  Title A 1-THz superconducting hot-electron-bolometer receiver for astronomical observations Type Journal Article
  Year 2004 Publication IEEE Trans. Microwave Theory Techn. Abbreviated Journal IEEE Trans. Microwave Theory Techn.  
  Volume 52 Issue 10 Pages 2338-2343  
  Keywords NbN HEB mixer, applications  
  Abstract In this paper, we describe a superconducting hot-electron-bolometer mixer receiver developed to operate in atmospheric windows between 800-1300 GHz. The receiver uses a waveguide mixer element made of 3-4-nm-thick NbN film deposited over crystalline quartz. This mixer yields double-sideband receiver noise temperatures of 1000 K at around 1.0 THz, and 1600 K at 1.26 THz, at an IF of 3.0 GHz. The receiver was successfully tested in the laboratory using a gas cell as a spectral line test source. It is now in use on the Smithsonian Astrophysical Observatory terahertz test telescope in northern Chile.  
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  Corporate Author Thesis  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0018-9480 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 1484  
Permanent link to this record
 
 
Author Meledin, D.; Tong, C.-Y. E.; Blundell, R.; Goltsman, G. url  doi
openurl 
  Title Measurement of intermediate frequency bandwidth of hot electron bolometer mixers at terahertz frequency range Type Journal Article
  Year 2003 Publication IEEE Microw. Wireless Compon. Lett. Abbreviated Journal IEEE Microw. Wireless Compon. Lett.  
  Volume 13 Issue 11 Pages 493-495  
  Keywords waveguide NbN HEB mixers  
  Abstract We have developed a new experimental setup for measuring the IF bandwidth of superconducting hot electron bolometer mixers. In our measurement system we use a chopped hot filament as a broadband signal source, and can perform a high-speed IF scan with no loss of accuracy when compared to coherent methods. Using this technique we have measured the 3 dB IF bandwidth of hot electron bolometer mixers, designed for THz frequency operation, and made from 3-4 nm thick NbN film deposited on an MgO buffer layer over crystalline quartz.  
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  Corporate Author Thesis  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1531-1309 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 1509  
Permanent link to this record
 
 
Author Miao, W.; Zhang, W.; Zhong, J. Q.; Shi, S. C.; Delorme, Y.; Lefevre, R.; Feret, A; Vacelet, T url  doi
openurl 
  Title Non-uniform absorption of terahertz radiation on superconducting hot electron bolometer microbridges Type Journal Article
  Year 2014 Publication Appl. Phys. Lett. Abbreviated Journal <ef><bf><bc>Appl. Phys. Lett.  
  Volume 104 Issue Pages 052605(1-4)  
  Keywords NbN HEB mixers, local oscillator power, RF nonuniform absorption  
  Abstract We interpret the experimental observation of a frequency-dependence of superconducting hot electron bolometer (HEB) mixers by taking into account the non-uniform absorption of the terahertz radiation on the superconducting HEB microbridge. The radiation absorption is assumed to be proportional to the local surface resistance of the HEB microbridge, which is computed using the Mattis-Bardeen theory. With this assumption the dc and mixing characteristics of a superconducting niobium-nitride (NbN) HEB device have been modeled at frequencies below and above the equilibrium gap frequency of the NbN film.  
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  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 935  
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