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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 (up) 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.  
  Address  
  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 1531-1309 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 1509  
Permanent link to this record
 
 
Author Loudkov, D.; Tong, C. Y. E.; Blundell, R.; Kaurova, N.; Grishina, E.; Voronov, B.; Gol'tsman, G. openurl 
  Title An investigation of the performance of the superconducting HEB슠mixer as a function of its RF슠embedding impedance Type Journal Article
  Year 2005 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal  
  Volume (up) 15 Issue 2 Pages 472-475  
  Keywords HEB mixer  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher IEEE 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 371  
Permanent link to this record
 
 
Author Baselmans, J. J. A.; Hajenius, M.; Gao, J. R.; Baryshev, A.; Kooi, J.; Klapwijk, T. M.; Voronov, B.; de Korte, P.; Gol'tsman, G. url  doi
openurl 
  Title NbN hot electron bolometer mixers: sensitivity, LO power, direct detection and stability Type Journal Article
  Year 2005 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.  
  Volume (up) 15 Issue 2 Pages 484-489  
  Keywords HEB mixers, direct detection effect, stability, Allan variance  
  Abstract 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. Both the receiver noise temperature and the gain bandwidth can be improved by a factor of 2 by cleaning the interface and adding an additional superconducting interlayer to the contact pad. Using this we obtain a double sideband receiver noise temperature of 950 K at 2.5 THz and 4.3 K, using a 0.4/spl times/4 /spl mu/m HEB mixer with a spiral antenna. At the same bias point, we obtain an IF gain bandwidth of 6 GHz. To comply with current demands on THz mixers for use in space based receivers we reduce the device size to 0.15/spl times/1 /spl mu/m and use a twin slot antenna. We report measurements of the noise temperature, LO power requirement, stability and the direct detection effect, using a mixer with a 1.6 THz twin slot antenna and a 1.462 THz solid state LO source with calibrated output power.  
  Address  
  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 546  
Permanent link to this record
 
 
Author Hajenius, M.; Barends, R.; Gao, J. R.; Klapwijk, T. M.; Baselmans, J. J. A.; Baryshev, A.; Voronov, B.; Gol'tsman, G. doi  openurl
  Title Local resistivity and the current-voltage characteristics of hot electron bolometer mixers Type Journal Article
  Year 2005 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.  
  Volume (up) 15 Issue 2 Pages 495-498  
  Keywords HEB mixer distributed model, HEB distributed model, distributed HEB model  
  Abstract Hot-electron bolometer devices, used successfully in low noise heterodyne mixing at frequencies up to 2.5 THz, have been analyzed. A distributed temperature numerical model of the NbN bridge, based on a local electron and a phonon temperature, is used to model pumped IV curves and understand the physical conditions during the mixing process. We argue that the mixing is predominantly due to the strongly temperature dependent local resistivity of the NbN. Experimentally we identify the origins of different transition temperatures in a real HEB device, suggesting the importance of the intrinsic resistive transition of the superconducting bridge in the modeling.  
  Address  
  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 980  
Permanent link to this record
 
 
Author Loudkov, D.; Tong, C.-Y. E.; Blundell, R.; Kaurova, N.; Grishina, E.; Voronov, B.; Gol’tsman, G. url  doi
openurl 
  Title An investigation of the performance of the superconducting HEB mixer as a function of its RF embedding impedance Type Journal Article
  Year 2005 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.  
  Volume (up) 15 Issue 2 Pages 472-475  
  Keywords waveguide NbN HEB mixers  
  Abstract We have conducted an investigation of the optimal embedding impedance for a waveguide superconducting hot-electron bolometric (HEB) mixer. Three mixer chip designs for 800 GHz, offering nominal embedding resistances of 70 /spl Omega/, 35 /spl Omega/, and 15 /spl Omega/, have been developed. We used both High Frequency Structure Simulator (HFSS) software and scale model impedance measurements in the design process. We subsequently fabricated HEB mixers to these designs using 3-4 nm thick NbN thin film. Receiver noise temperature measurements and Fourier Transform Spectrometer (FTS) scans were performed to determine the optimal combination of embedding impedance and normal-state resistance for a 50 Ohm IF load impedance. A receiver noise temperature of 440 K was measured at a local oscillator frequency 850 GHz for a mixer with normal state resistance of 62 /spl Omega/ incorporated into a circuit offering a nominal embedding impedance of 70 /spl Omega/. We conclude from our data that, for low noise operation, the normal state resistance of the HEB mixer element should be close to the embedding impedance of the mixer mount.  
  Address  
  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 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number 1439677 Serial 1464  
Permanent link to this record
 
 
Author Baubert, J.; Salez, M.; Merkel, H.; Pons, P.; Cherednichenko, S.; Lecomte, B.; Drakinsky, V.; Goltsman, G.; Leone, B. url  doi
openurl 
  Title IF gain bandwidth of membrane-based NbN hot electron bolometers for SHAHIRA Type Journal Article
  Year 2005 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.  
  Volume (up) 15 Issue 2 Pages 507-510  
  Keywords NbN HEB mixers, applications  
  Abstract SHAHIRA (Submm Heterodyne Array for HIgh-speed Radio Astronomy) is a project supported by the European Space Agency (ESA) and is designed to fly on the SOFIA observatory. A quasi-optic design has been chosen for 2.5/2.7 THz and 4.7 THz, for hydroxyde radical OH, deuterated hydrogen HD and neutral atomic oxygen OI lines observations. Hot electron bolometers (HEBs) have been processed on 1 /spl mu/m thick SiO/sub 2//Si/sub 3/N/sub 4/ stress-less membranes. In this paper we analyse the intermediate frequency (IF) gain bandwidth from the theoretical point of view, and compare it to measurements.  
  Address  
  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 1558-2515 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 1468  
Permanent link to this record
 
 
Author Jiang, L.; Li, J.; Zhang, W.; Yao, Q. J.; Lin, Z. L.; Shi, S. C.; Vachtomin, Y. B.; Antipov, S. V.; Svechnikov, S. I.; Voronov, B. M.; Goltsman, G. N. url  doi
openurl 
  Title Characterization of NbN HEB mixers cooled by a close-cycled 4 Kelvin refrigerator Type Journal Article
  Year 2005 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.  
  Volume (up) 15 Issue 2 Pages 511-513  
  Keywords NbN HEB mixers  
  Abstract It is quite beneficial to operate superconducting hot-electron-bolometer (HEB) mixers with a close-cycled 4 Kelvin refrigerator for real applications such as astronomy and atmospheric research. In this paper, a phononcooled NbN HEB mixer (quasioptical type) is thoroughly characterized under such a cooling circumstance. The effects of mechanical vibration, electrical interference, and temperature fluctuation of a two-stage Gifford-McMahon 4 Kelvin refrigerator upon the characteristics of the phononcooled NbN HEB mixer are investigated in particular. Detailed measurement results are presented.  
  Address  
  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 1558-2515 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 1469  
Permanent link to this record
 
 
Author Hajenius, M.; Baselmans, J. J. A.; Gao, J. R.; Klapwijk, T. M.; de Korte, P. A. J.; Voronov, B.; Gol'tsman, G. url  doi
openurl 
  Title Low noise NbN superconducting hot electron bolometer mixers at 1.9 and 2.5 THz Type Journal Article
  Year 2004 Publication Supercond. Sci. Technol. Abbreviated Journal Supercond. Sci. Technol.  
  Volume (up) 17 Issue 5 Pages S224-S228  
  Keywords NbN HEB mixers  
  Abstract NbN phonon-cooled hot electron bolometer mixers (HEBs) have been realized with negligible contact resistance between the bolometer itself and the contact structure. Using a combination of in situ cleaning of the NbN film and the use of an additional superconducting interlayer of a 10 nm NbTiN layer between the Au of the contact structure and the NbN film superior noise temperatures have been obtained as low as 950 K at 2.5 THz and 750 K at 1.9 THz. Here we address in detail the DC characterization of these devices, the interface transparencies between the bolometers and the contacts and the consequences of these factors on the mixer performance.  
  Address  
  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 0953-2048 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 558  
Permanent link to this record
 
 
Author Semenov, Alexei; Richter, Heiko; Smirnov, Konstantin; Voronov, Boris; Gol'tsman, Gregory; Hübers, Heinz-Wilhelm doi  openurl
  Title The development of terahertz superconducting hot-electron bolometric mixers Type Journal Article
  Year 2004 Publication Supercond. Sci. Technol. Abbreviated Journal Supercond. Sci. Technol.  
  Volume (up) 17 Issue 5 Pages 436-439  
  Keywords NbN HEB mixers  
  Abstract We present recent advances in the development of NbN hot-electron bolometric (HEB) mixers for flying terahertz heterodyne receivers. Three important issues have been addressed: the quality of the source NbN films, the effect of the bolometer size on the spectral properties of different planar feed antennas, and the local oscillator (LO) power required for optimal operation of the mixer. Studies of the NbN films with an atomic force microscope indicated a surface structure that may affect the performance of the smallest mixers. Measured spectral gain and noise temperature suggest that at frequencies above 2.5 THz the spiral feed provides better overall performance than the double-slot feed. Direct measurements of the optimal LO power support earlier estimates made in the framework of the uniform mixer model.  
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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 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 357  
Permanent link to this record
 
 
Author Rabanus, D.; Graf, U. U.; Philipp, M.; Ricken, O.; Stutzki, J.; Vowinkel, B.; Wiedner, M. C.; Walther, C.; Fischer, M.; Faist, J. openurl 
  Title Phase locking of a 1.5 terahertz quantum cascade laser and use as a local oscillator in a heterodyne HEB receiver Type Journal Article
  Year 2009 Publication Optics Express Abbreviated Journal  
  Volume (up) 17 Issue 3 Pages 1159-1168  
  Keywords QCL heterodyne, 300 uW at 1.5 THz, HEB mixer  
  Abstract We demonstrate for the first time the closure of an electronic phase lock loop for a continuous–wave quantum cascade laser (QCL) at 1.5 THz. The QCL is operated in a closed cycle cryo cooler. We achieved a frequency stability of better than 100 Hz, limited by the resolution bandwidth of the spectrum analyser. The PLL electronics make use of the intermediate frequency (IF) obtained from a hot electron bolometer (HEB) which is downconverted to a PLL IF of 125 MHz. The coarse selection of the longitudinal mode and the fine tuning is achieved via the bias voltage of the QCL. Within a QCL cavity mode, the free-running QCL shows frequency fluctuations of about 5 MHz, which the PLL circuit is able to control via the Stark–shift of the QCL gain material. Temperature dependent tuning is shown to be nonlinear, and of the order of -16 MHz/K. Additionally we have used the QCL as local oscillator (LO) to pump an HEB and perform, again for the first time at 1.5 THz, a heterodyne experiment, and obtain a receiver noise temperature of 1741 K.  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 628  
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