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0kunev, 0.; Dzardanov, A.; Ekstrom, H.; Jacobsson, S.; Kollberg, E.; Gol'tsman, G.; Gershenzon, E. |
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Title |
NbN hot electron waveguide mixer for 100 GHz operation |
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Conference Article |
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Year |
1994 |
Publication |
Proc. 5th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 5th Int. Symp. Space Terahertz Technol. |
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214-224 |
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waveguide NbN HEB mixers |
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Abstract |
NbN is a promising superconducting material used to develope hot- electron superconducting mixers with an IF bandwidth over 1 GHz. In the 100 GHz frequency range, the following parameters were obtained for NbN films 50 A thick: the noise temperature of the receiver (DSB) 1000 K; the conversion losses 10 d13, the IF bandwidth 1 GHz; the local oscillator power 1 /LW. An increase of NbN film thickness up to 80-100 A and increase of working temperature up to 7-8 K, and a better mixer matching may allow to broader the IF band up to 3 Gllz, to reduce the conversion losses down to 3-5 dB and the noise tempera- ture down to 200-300 K. |
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1644 |
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Gol'tsman, G.; Maslennikov, S.; Finkel, M.; Antipov, S.; Kaurova, N.; Grishina, E.; Polyakov, S.; Vachtomin, Y.; Svechnikov, S.; Smirnov, K.; Voronov, B. |
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Title |
Nanostructured ultrathin NbN film as a terahertz hot-electron bolometer mixer |
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Conference Article |
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Year |
2006 |
Publication |
Proc. MRS |
Abbreviated Journal |
Proc. MRS |
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Volume |
935 |
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210 (1 to 6) |
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Keywords |
NbN HEB mixers |
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Abstract |
Planar spiral antenna coupled and directly lens coupled NbN HEB mixer structures are studied. An additional MgO buffer layer between the superconducting film and Si substrate is introduced. The buffer layer enables us to increase the gain bandwidth of a HEB mixer due to better acoustic transparency. The gain bandwidth is widened as NbN film thickness decreases and amounts to 5.2 GHz. The noise temperature of antenna coupled mixer is 1300 and 3100 K at 2.5 and 3.8 THz respectively. The structure and composition of NbN films is investigated by X-ray diffraction spectroscopy methods. Noise performance degradation at LO frequencies more than 3 THz is due to the use of a planar antenna and signal loss in contacts between the antenna and the sensitive NbN bridge. The mixer is reconfigured for operation at higher frequencies in a manner that receiver’s noise temperature is only 2300 K (3 times of quantum limit) at LO frequency of 30 THz. |
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0272-9172 |
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1440 |
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Zhang, W.; Jiang, L.; Lin, Z. H.; Yao, Q. J.; Li, J.; Shi, S. C.; Svechnikov, S. I.; Vachtomin, Yu. B.; Antipov, S. V.; Voronov, B. M.; Kaurova, N. S.; Gol'tsman, G. N. |
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Title |
Development of a quasi-optical NbN superconducting HEB mixer |
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Conference Article |
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Year |
2005 |
Publication |
Proc. 16th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 16th Int. Symp. Space Terahertz Technol. |
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209-213 |
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Keywords |
NbN HEB mixers |
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In this paper, we report the performance of a quasi-optical NbN superconducting HEB (hot electron bolometer) mixer measured at 500 and 850GHz. The quasi-optical NbN superconducting HEB mixer is cryogenically cooled by a 4-K close-cycled refrigerator. Measured receiver noise temperature at 850 and 500GHz are 3000K and 2500K respectively with wire grid as beamsplitter, while the lowest receiver noise temperature is found to be approximately 1200K with Mylar film. The theoretical receiver noise temperature (taking into account the elliptical polarization of log-spiral antenna) is consistent with measured one. The receiver noise temperature and conversion gain with 15-μm Mylar film as the beamsplitter at 500GHz are thoroughly investigated for different LO pumping levels and dc biases. The stability of the mixer’s IF output power is also demonstrated. |
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1470 |
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Gol'tsman, G.; Jacobsson, S.; Ekstrom, H.; Karasik, B.; Kollberg, E.; Gershenzon, E. |
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Title |
Slot-line tapered antenna with NbN hot electron mixer for 300-360 GHz operation |
Type |
Conference Article |
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Year |
1994 |
Publication |
Proc. 5th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 5th Int. Symp. Space Terahertz Technol. |
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Pages |
209-213a |
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Keywords |
NbN HEB mixers |
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NbN hot-electron mixers combined with slot-line tapered antennas on Si wdnitride membranes had been fabricated. Several strips of 1 gm wide and 5 tan long made from 100 A NbN film are inserted into the slot antenna. IV-curves under local oscillator power in 300-350 GHz frequency range and conversion gain dependencies on intermediate fre- quency in the 0.1-1 GHz range are measured and compared with that for 100 GHz frequency band. Our results show that pumped IV-curves and intermediate frequency bands are different for 100 GHz and 300 GHz frequency ranges. The interpretation exploits the fact that for the lowest radiation frequency the superconducting energy gap is larger than the radiation quantum energy while they are comparable at the higher frequency. Tha results show that such mixers have good perspectives for terahertz receiving technology. |
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1643 |
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Ekström, H.; Kroug, M.; Belitsky, V.; Kollberg, E.; Olsson, H.; Goltsman, G.; Gershenzon, E.; Yagoubov, P.; Voronov, B.; Yngvesson, S. |
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Title |
Hot electron mixers for THz applications |
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Conference Article |
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Year |
1996 |
Publication |
Proc. 30th ESLAB |
Abbreviated Journal |
Proc. 30th ESLAB |
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207-210 |
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Keywords |
NbN HEB mixers |
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Abstract |
We have measured the noise performance of 35 A thin NbN HEB devices integrated with spiral antennas on antireflection coated silicon substrate lenses at 620 GHz. From the noise measurements we have determined a total conversion gain of the receiver of—16 dB, and an intrinsic conversion of about-10 dB. The IF bandwidth of the 35 A thick NbN devices is at least 3 GHz. The DSB receiver noise temperature is less than 1450 K. Without mismatch losses, which is possible to obtain with a shorter device, and with reduced loss from the beamsplitter, we expect to achieve a DSB receiver noise temperature of less ‘than 700 K. |
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Noordwijk, Netherlands |
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Rolfe, E. J.; Pilbratt, G. |
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Submillimetre and Far-Infrared Space Instrumentation |
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1606 |
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Svechnikov, S. I.; Antipov, S. V.; Vakhtomin, Y. B.; Goltsman, G. N.; Gershenzon, E. M.; Cherednichenko, S. I.; Kroug, M.; Kollberg, E. |
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Conversion and noise bandwidths of terahertz NbN hot-electron bolometer mixers |
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Journal Article |
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2001 |
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Physics of Vibrations |
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Physics of Vibrations |
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9 |
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3 |
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205-210 |
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NbN HEB mixers |
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1069-1227 |
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1551 |
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Semenov, A. D.; Hübers, H.-W.; Gol’tsman, G. N.; Smirnov, K. |
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Superconducting quantum detector for astronomy and X-ray spectroscopy |
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Conference Article |
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2002 |
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Proc. Int. Workshop on Supercond. Nano-Electronics Devices |
Abbreviated Journal |
Proc. Int. Workshop on Supercond. Nano-Electronics Devices |
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201-210 |
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NbN SSPD, SNSPD, SQD, superconducting quantum detectors, X-ray spectroscopy |
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We propose the novel concept of ultra-sensitive energy-dispersive superconducting quantum detectors prospective for applications in astronomy and X-ray spectroscopy. Depending on the superconducting material and operation conditions, such detector may allow realizing background limited noise equivalent power 10−21 W Hz−1/2 in the terahertz range when exposed to 4-K background radiation or counting of 6-keV photon with almost 10—4 energy resolution. Planar layout and relatively simple technology favor integration of elementary detectors into a detector array. |
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Naples, Italy |
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Springer |
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Boston, MA |
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Pekola, J.; Ruggiero, B.; Silvestrini, P. |
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978-1-4615-0737-6 |
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International Workshop on Superconducting Nano-Electronics Devices, May 28-June 1, 2001 |
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semenov2002superconducting |
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1525 |
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Gerecht, E.; Musante, C. F.; Jian, H.; Zhuang, Y.; Yngvesson, K. S.; Dickinson, J.; Goyette, T.; Waldman, J.; Yagoubov, P. A.; Gol'tsman, G. N.; Voronov, B. M.; Gershenzon, E. M. |
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Improved characteristics of NbN HEB mixers integrated with log-periodic antennas |
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Conference Article |
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1999 |
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Proc. 10th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 10th Int. Symp. Space Terahertz Technol. |
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200-207 |
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NbN HEB mixers |
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1574 |
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Author |
Gol'tsman, G. N. |
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Title |
Hot electron bolometric mixers: new terahertz technology |
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Journal Article |
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1999 |
Publication |
Infrared Physics & Technology |
Abbreviated Journal |
Infrared Physics & Technology |
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Volume |
40 |
Issue |
3 |
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199-206 |
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NbN HEB mixers |
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This paper presents an overview of recent results for NbN phonon-cooled hot electron bolometric (HEB) mixers. The noise temperature of the receivers based on both quasioptical and waveguide versions of HEB mixers has crossed the level of 1 K GHz−1 at 430 GHz (410 K), 600–650 GHz (480 K), 750 GHz (600 K), 810 GHz (780 K) and is close to that level at 1.1 THz (1250 K) and 2.5 THz (4500 K). The gain bandwidth measured for quasioptical HEB mixer at 620 GHz reached 4 GHz and the noise temperature bandwidth was almost 8 GHz. Local oscillator power requirements are about 1 μW for mixers made by photolithography and about 100 nW for mixers made by e-beam lithography. A waveguide version of 800 GHz receiver was installed at the Submillimeter Telescope Observatory on Mt. Graham, AZ, to conduct astronomical observations of known submillimeter lines (CO, J=7→6, CI, J=2→1). It was proved that the receiver works as a practical instrument. |
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1350-4495 |
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1570 |
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Huebers, H.-W.; Semenov, A.; Schubert, J.; Gol’tsman, G. N.; Voronov, B. M.; Gershenzon, E. M.; Krabbe, A.; Roeser, H.-P. |
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Title |
NbN hot-electron bolometer as THz mixer for SOFIA |
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Conference Article |
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2000 |
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Proc. SPIE |
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Proc. SPIE |
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4014 |
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195-202 |
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NbN HEB mixers, airborne, stratospheric observatory, SOFIA |
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Heterodyne receivers for applications in astronomy need quantum limited sensitivity. We have investigated phonon- cooled NbN hot electron bolometric mixers in the frequency range from 0.7 THz to 5.2 THz. The devices were 3.5 nm thin films with an in-plane dimension of 1.7 X 0.2 micrometers 2 integrated in a complementary logarithmic spiral antenna. The best measured DSB receiver noise temperatures are 1300 K (0.7 THz), 2000 K (1.4 THz), 2100 K (1.6 THz), 2600 K (2.5 THz), 4000 K (3.1 THz), 5600 K (4.3 THz), and 8800 K (5.2 THz). The sensitivity fluctuation, the long term stability, and the antenna pattern were measured. The results demonstrate that this mixer is very well suited for GREAT, the German heterodyne receiver for SOFIA. |
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SPIE |
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Melugin, R.K.; Roeser, H.-P. |
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Airborne Telescope Systems |
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1554 |
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Author |
Ryabchun, Sergey; Tong, Cheuk-yu Edward; Blundell, Raymond; Kimberk, Robert; Gol’tsman, Gregory |
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Title |
Stabilisation of a terahertz hot-electron bolometer mixer with microwave feedback control |
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Conference Article |
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2007 |
Publication |
Proc. 18th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 18th Int. Symp. Space Terahertz Technol. |
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193-198 |
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waveguide NbN HEB mixers, Allan variance, stability |
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We report on implementation of microwave feedback control loop to stabilise the performance of an HEB mixer receiver. It is shown that the receiver sensitivity increases by a factor of 4 over a 16-minute scan, and the corresponding Allan time increases up to 10 seconds, as opposed to an open loop value of 1 second. Our experiments also demonstrate that the receiver sensitivity is limited by the intermediate frequency chain. |
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1421 |
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Gol’tsman, G. N.; Smirnov, K.; Kouminov, P.; Voronov, B.; Kaurova, N.; Drakinsky, V.; Zhang, J.; Verevkin, A.; Sobolewski, R. |
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Fabrication of nanostructured superconducting single-photon detectors |
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Journal Article |
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2003 |
Publication |
IEEE Trans. Appl. Supercond. |
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IEEE Trans. Appl. Supercond. |
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13 |
Issue |
2 |
Pages |
192-195 |
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NbN SSPD, SNSPD |
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Fabrication of NbN superconducting single-photon detectors, based on the hotspot effect is presented. The hotspot formation arises in an ultrathin and submicrometer-width superconductor stripe and, together with the supercurrent redistribution, leads to the resistive detector response upon absorption of a photon. The detector has a meander structure to maximally increase its active area and reach the highest detection efficiency. Main processing steps, leading to efficient devices, sensitive in 0.4-5 /spl mu/m wavelength range, are presented. The impact of various processing steps on the performance and operational parameters of our detectors is discussed. |
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1558-2515 |
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1515 |
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Schubert, J.; Semenov, A.; Gol'tsman, G.; Hübers, H.-W.; Schwaab, G.; Voronov, B.; Gershenzon, E. |
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Title |
Noise temperature and sensitivity of a NbN hot-electron mixer at frequencies from 0.7 THz to 5.2 THz |
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Conference Article |
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1999 |
Publication |
Proc. 10th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 10th Int. Symp. Space Terahertz Technol. |
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190-199 |
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Keywords |
NbN HEB mixers |
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We report on noise temperature measurements of a NbN phonon-cooled hot-electron bolometric mixer at different bias regimes. The device was a 3 nm thick bridge with in-plane dimensions of 1.7 x 0.2 gm 2 integrated in a complementary logarithmic spiral antenna. Measurements were performed at frequencies ranging from 0.7 THz up to 5.2 THz. The measured DSB noise temperatures are 1500 K (0.7 THz), 2200 K (1.4 THz), 2600 K (1.6 THz), 2900 K (2.5 THz), 4000 K (3.1 THz) 5600 K (4.3 THz) and 8800 K (5.2 THz). Two bias regimes are possible in order to achieve low noise temperatures. But only one of them yields sensitivity fluctuations close to the theoretical limit. |
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Gao, J. R.; Hajenius, M.; Tichelaar, F. D.; Voronov, B.; Grishina, E.; Klapwijk, T. M.; Gol'tsman, G.; Zorman, C. A. |
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Can NbN films on 3C-SiC/Si change the IF bandwidth of hot electron bolometer mixers? |
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2006 |
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Proc. 17th Int. Symp. Space Terahertz Technol. |
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Proc. 17th Int. Symp. Space Terahertz Technol. |
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187-189 |
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NbN HEB mixers |
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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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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. |
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Development of HEB mixers for GREAT and for security screening |
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2007 |
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Proc. 18th Int. Symp. Space Terahertz Technol. |
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Proc. 18th Int. Symp. Space Terahertz Technol. |
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184 |
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NbN HEB mixers, GREAT |
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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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