| Records |
| Author |
Zhang, W.; Miao, W.; Zhong, J. Q.; Shi, S. C.; Hayton, D. J.; Vercruyssen, N.; Gao, J. R.; Goltsman, G. N. |
| Title |
Temperature dependence of the receiver noise temperature and IF bandwidth of superconducting hot electron bolometer mixers |
Type |
Journal Article |
Year  |
2014 |
Publication |
Supercond. Sci. Technol. |
Abbreviated Journal |
Supercond. Sci. Technol. |
| Volume |
27 |
Issue |
8 |
Pages |
085013 (1 to 5) |
| Keywords |
NbN HEB mixers |
| Abstract |
In this paper we study the temperature dependence of the receiver noise temperature and IF noise bandwidth of superconducting hot electron bolometer (HEB) mixers. Three superconducting NbN HEB devices of different transition temperatures (Tc) are measured at 0.85 THz and 1.4 THz at different bath temperatures (Tbath) between 4 K and 9 K. Measurement results demonstrate that the receiver noise temperature of superconducting NbN HEB devices is nearly constant for Tbath/Tc, less than 0.8, which is consistent with the simulation based on a distributed hot-spot model. In addition, the IF noise bandwidth appears independent of Tbath/Tc, indicating the dominance of phonon cooling in the investigated HEB devices. |
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0953-2048 |
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no |
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1358 |
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| Author |
Zhang, W.; Miao, W.; Zhong, J. Q.; Shi, S. C.; Hayton, D. J.; Vercruyssen, N.; Gao, J. R.; Goltsman, G. N. |
| Title |
Temperature dependence of superconducting hot electron bolometers |
Type |
Conference Article |
| Year |
2013 |
Publication |
Not published results: 24th international symposium on space terahertz technology |
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Pages |
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| Keywords |
HEB |
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| Address |
Groningen,The Netherlands |
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no |
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Serial |
1067 |
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Zhang, W.; Miao, W.; Li, S. L.; Zhou, K. M.; Shi, S. C.; Gao, J. R.; Goltsman, G. N. |
| Title |
Measurement of the spectral response of spiral-antenna coupled superconducting hot electron bolometers |
Type |
Journal Article |
| Year |
2013 |
Publication |
IEEE Trans. Appl. Supercond. |
Abbreviated Journal |
IEEE Trans. Appl. Supercond. |
| Volume |
23 |
Issue |
3 |
Pages |
2300804-2300804 |
| Keywords |
NbN HEB detector |
| Abstract |
Measured spectral response of spiral-antenna coupled superconducting hot electron bolometers (HEBs) often drops dramatically at frequencies that are still within the frequency range of interest (e.g., ~ 5 THz). This is inconsistent with the implied low receiver noise temperatures from the same measurements. To understand this discrepancy, we exhaustively test and calibrate the thermal sources used in Fourier transform spectrometer measurements. We first investigate the absolute emission spectrum of high-pressure Hg arc lamp, then measure the spectral response of two spiral-antenna coupled NbN HEBs with a Martin-Puplett interferometer as spectrometer and 77 K blackbody as broadband signal source. The measured absolute emission spectrum of Hg arc lamp is proportional to frequency, corresponding to an equivalent blackbody temperature of 4000 K at 1 THz, 1500 K at 3 THz, and 800 K at 5 THz, respectively. Measured spectral response of spiral-antenna coupled NbN HEBs, corrected for air absorption, is nearly flat in the frequency range of 0.5-4 THz, consistent with simulated coupling efficiency between HEB and spiral-antenna. These results explain the discrepancy, and prove that spiral-antenna coupled superconducting NbN HEBs work well in a wide frequency range. In addition, this calibration method and these results are broadly applicable to other quasi-optical THz receivers. |
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1051-8223 |
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no |
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Serial |
1371 |
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| Author |
Zhang, W.; Miao, W.; Yao, Q. J.; Lin, Z. H.; Shi, S. C.; Gao, J. R.; Goltsman, G. N. |
| Title |
Spectral response and noise temperature of a 2.5 THz spiral antenna coupled NbN HEB mixer |
Type |
Journal Article |
| Year |
2012 |
Publication |
Phys. Procedia |
Abbreviated Journal |
Phys. Procedia |
| Volume |
36 |
Issue |
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Pages |
334-337 |
| Keywords |
NbN HEB mixer |
| Abstract |
We report on a 2.5 THz spiral antenna coupled NbN hot electron bolometer (HEB) mixers, fabricated with in-situ process. The receiver noise temperature with lowest value of 1180 K is in good agreement with calculated quantum efficiency factor as a function of bias voltage. In addition, the measured spectral response of the spiral antenna coupled NbN HEB mixer shows broad frequency coverage of 0.8-3 THz, and corrected response for optical losses, FTS, and coupling efficiency between antenna and bolometer falls with frequency due to diffraction-limited beam of lens/antenna combination. |
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Edition |
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| ISSN |
1875-3892 |
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no |
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Serial |
1381 |
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Zhang, W.; Khosropanah, P.; Gao, J. R.; Kollberg, E. L.; Yngvesson, K. S.; Bansal, T.; Barends, R.; Klapwijk, T. M. |
| Title |
Quantum noise in a terahertz hot electron bolometer mixer |
Type |
Journal Article |
| Year |
2010 |
Publication |
Applied Physics Letters |
Abbreviated Journal |
Appl. Phys. Lett. |
| Volume |
96 |
Issue |
11 |
Pages |
111113-(1-3) |
| Keywords |
HEB mixer, quantum limit, quantum noise, vacuum box, THz, Terahertz |
| Abstract |
We have measured the noise temperature of a single, sensitive superconducting NbN hot electron bolometer (HEB) mixer in a frequency range from 1.6 to 5.3 THz, using a setup with all the key components in vacuum. By analyzing the measured receiver noise temperature using a quantum noise (QN) model for HEB mixers, we confirm the effect of QN. The QN is found to be responsible for about half of the receiver noise at the highest frequency in our measurements. The beta-factor (the quantum efficiency of the HEB) obtained experimentally agrees reasonably well with the calculated value. |
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no |
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Serial |
624 |
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| Author |
Wild, W.; Kardashev, N. S.; Likhachev, S. F.; Babakin, N. G.; Arkhipov, V. Y.; Vinogradov, I. S.; Andreyanov, V. V.; Fedorchuk, S. D.; Myshonkova, N. V.; Alexsandrov, Y. A.; Novokov, I. D.; Goltsman, G. N.; Cherepaschuk, A. M.; Shustov, B. M.; Vystavkin, A. N.; Koshelets, V. P.; Vdovin, V.F.; de Graauw, T.; Helmich, F.; vd Tak, F.; Shipman, R.; Baryshev, A.; Gao, J. R.; Khosropanah, P.; Roelfsema, P.; Barthel, P.; Spaans, M.; Mendez, M.; Klapwijk, T.; Israel, F.; Hogerheijde, M.; vd Werf, P.; Cernicharo, J.; Martin-Pintado, J.; Planesas, P.; Gallego, J. D.; Beaudin, G.; Krieg, J. M.; Gerin, M.; Pagani, L.; Saraceno, P.; Di Giorgio, A. M.; Cerulli, R.; Orfei, R.; Spinoglio, L.; Piazzo, L.; Liseau, R.; Belitsky, V.; Cherednichenko, S.; Poglitsch, A.; Raab, W.; Guesten, R.; Klein, B.; Stutzki, J.; Honingh, N.; Benz, A.; Murphy, A.; Trappe, N.; Räisänen, A. |
| Title |
Millimetron—a large Russian-European submillimeter space observatory |
Type |
Journal Article |
| Year |
2009 |
Publication |
Exp. Astron. |
Abbreviated Journal |
Exp. Astron. |
| Volume |
23 |
Issue |
1 |
Pages |
221-244 |
| Keywords |
Millimetron space observatory, VLBI, very long baseline interferometry |
| Abstract |
Millimetron is a Russian-led 12 m diameter submillimeter and far-infrared space observatory which is included in the Space Plan of the Russian Federation for launch around 2017. With its large collecting area and state-of-the-art receivers, it will enable unique science and allow at least one order of magnitude improvement with respect to the Herschel Space Observatory. Millimetron will be operated in two basic observing modes: as a single-dish observatory, and as an element of a ground-space very long baseline interferometry (VLBI) system. As single-dish, angular resolutions on the order of 3 to 12 arc sec will be achieved and spectral resolutions of up to a million employing heterodyne techniques. As VLBI antenna, the chosen elliptical orbit will provide extremely large VLBI baselines (beyond 300,000 km) resulting in micro-arc second angular resolution. |
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0922-6435 |
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no |
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Serial |
1402 |
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| Author |
Khosropanah, P.; Gao, J. R.; Laauwen, W. M.; Hajenius, M; Klapwijk, T. M. |
| Title |
Low noise NbN hot electron bolometer mixer at 4.3 THz |
Type |
Journal Article |
| Year |
2007 |
Publication |
Appl. Phys. Lett. |
Abbreviated Journal |
Appl. Phys. Lett. |
| Volume |
91 |
Issue |
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Pages |
221111 (1 to 3) |
| Keywords |
NbN HEB mixers, NbN, contacts cleaning |
| Abstract |
We have studied the sensitivity of a superconducting NbN hot electron bolometer mixer integrated with a spiral antenna at 4.3 THz. Using hot/cold blackbody loads and a beam splitter all in vacuum, we measured a double sideband receiver noise temperature of 1300 K at the optimum local oscillator (LO) power of 330 nW, which is about 12 times the quantum noise (hnu/2kB). Our result indicates that there is no sign of degradation of the mixing process at the superterahertz frequencies. Moreover, a measurement method is introduced which allows us for an accurate determination of the sensitivity despite LO power fluctuations. |
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no |
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Serial |
584 |
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| Author |
Kooi, J. W.; Baselmans, J. J. A.; Hajenius, M.; Gao, J. R.; Klapwijk, T. M.; Dieleman, P.; Baryshev, A.; de Lange, G. |
| Title |
IF impedance and mixer gain of NbN hot electron bolometers |
Type |
Journal Article |
| Year |
2007 |
Publication |
J. Appl. Phys. |
Abbreviated Journal |
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| Volume |
101 |
Issue |
4 |
Pages |
044511 |
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0021-8979 |
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no |
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RPLAB @ s @ |
Serial |
445 |
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Gao, J. R.; Hajenius, M.; Yang, Z. Q.; Baselmans, J. J. A.; Khosropanah, P.; Barends, R.; Klapwijk, T. M. |
| Title |
Terahertz superconducting hot electron bolometer heterodyne receivers |
Type |
Journal Article |
| Year |
2007 |
Publication |
IEEE Trans. Appl. Supercond. |
Abbreviated Journal |
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| Volume |
17 |
Issue |
2 |
Pages |
252-258 |
| Keywords |
HEB, mixer, direct detection effect |
| Abstract |
We highlight the progress on NbN hot electron bolometer (HEB) mixers achieved through fruitful collaboration between SRON Netherlands Institute for Space Research and Delft University of Technology, the Netherlands. This includes the best receiver noise temperatures of 700 K at 1.63 THz using a twin-slot antenna mixer and 1050 K at 2.84 THz using a spiral antenna coupled HEB mixer. The mixers are based on thin NbN films on Si and fabricated with a new contact-process and-structure. By reducing their areas HEB mixers have shown an LO power requirement as low as 30 nW. Those small HEB mixers have demonstrated equivalent sensitivity as those with large areas provided the direct detection effect due to broadband radiation is removed. To manifest that a HEB based heterodyne receiver can in practice be used at arbitrary frequencies above 2 THz, we demonstrate a 2.8 THz receiver using a THz quantum cascade laser (QCL) as local oscillator. |
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1051-8223 |
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no |
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RPLAB @ asmirn @ |
Serial |
557 |
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Hajenius, M.; Yang, Z. Q.; Gao, J. R.; Baselmans, J. J. A.; Klapwijk, T. M.; Voronov, B.; Gol'tsman, G. |
| 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. |
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1051-8223 |
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no |
| Call Number |
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Serial |
1426 |
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| Author |
Gao, J. R.; Hajenius, M.; Tichelaar, F. D.; Klapwijk, T. M.; Voronov, B.; Grishin, E.; Gol’tsman, G.; Zorman, C. A.; Mehregany, M. |
| Title |
Monocrystalline NbN nanofilms on a 3C-SiC∕Si substrate |
Type |
Journal Article |
| Year |
2007 |
Publication |
Appl. Phys. Lett. |
Abbreviated Journal |
Appl. Phys. Lett. |
| Volume |
91 |
Issue |
6 |
Pages |
062504 (1 to 3) |
| Keywords |
NbN films, nanofilms |
| Abstract |
The authors have realized NbN (100) nanofilms on a 3C-SiC (100)/Si(100) substrate by dc reactive magnetron sputtering at 800°C. High-resolution transmission electron microscopy (HRTEM) is used to characterize the films, showing a monocrystalline structure and confirming epitaxial growth on the 3C-SiC layer. A film ranging in thickness from 3.4to4.1nm shows a superconducting transition temperature of 11.8K, which is the highest reported for NbN films of comparable thickness. The NbN nano-films on 3C-SiC offer a promising alternative to improve terahertz detectors. For comparison, NbN nanofilms grown directly on Si substrates are also studied by HRTEM.
The authors acknowledge S. V. Svetchnikov at National Centre for HRTEM at Delft, who prepared the specimens for HRTEM inspections. This work was supported by the EU through RadioNet and INTAS. |
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0003-6951 |
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no |
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1425 |
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Hajenius, M.; Baselmans, J. J. A.; Baryshev, A.; Gao, J. R.; Klapwijk, T. M.; Kooi, J. W.; Jellema, W.; Yang, Z. Q. |
| Title |
Full characterization and analysis of a terahertz heterodyne receiver based on a NbN hot electron bolometer |
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Journal Article |
| Year |
2006 |
Publication |
J. Appl. Phys. |
Abbreviated Journal |
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| Volume |
100 |
Issue |
7 |
Pages |
074507 |
| Keywords |
HEB |
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0021-8979 |
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no |
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RPLAB @ s @ |
Serial |
385 |
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Gao, J.R.; Hiajenius, M.; Yang, Z.Q.; Klapwijk, T.M.; Miao, W.; Shi, S. C.; Voronov, B.; Gortsman, G. |
| Title |
Direct comparison of the sensitivity of a spiral and a twin-slot antenna coupled HEB mixer at 1.6 THz |
Type |
Conference Article |
| Year |
2006 |
Publication |
Proc. 17th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 17th Int. Symp. Space Terahertz Technol. |
| Volume |
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Issue |
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Pages |
59-62 |
| Keywords |
NbN HEB mixers |
| Abstract |
To make a direct comparison of the sensitivity between a spiral and a twin slot antenna coupled HEB mixer, we designed both types of mixers and fabricated them in a single processing run and on the same wafer. Both mixers have similar dimensions of NbN bridges (1.5-2 pm x0.2 pm). At 1.6 THz we obtained a nearly identical receiver noise temperature from both mixers (only 5% difference), which is in a good agreement with the simulation based on semi analytical models for both antennas. In addition, by using a bandpass filter to reduce the direct detection effect and lowering the bath temperature to 2.4 K, we measured the lowest receiver noise temperature of 700 K at 1.63 THz using the twin-slot antenna mixer. |
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no |
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Serial |
1436 |
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Baselmans, J. J. A.; Baryshev, A.; Hajenius, M.; Gao, J. R.; Klapwijk, T. M.; Voronov, B.; Gol'tsman, G. |
| Title |
Influence of the direct response on the heterodyne sensitivity of hot electron bolometer mixers |
Type |
Abstract |
| Year |
2006 |
Publication |
Proc. 17th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 17th Int. Symp. Space Terahertz Technol. |
| Volume |
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Issue |
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Pages |
81 |
| Keywords |
NbN HEB mixers |
| Abstract |
We present a detailed experimental study of the direct detection effect in a small volume (0.15pm x lpm) NbN hot electron bolometer mixer. It is a quasioptical mixer with a twin slot antenna designed for 700 GHz and the measurement was done at a LO frequency of 670 GHz. The direct detection effect is characterized by a change in the mixer bias current when switching broadband radiation from a 300 K hot load to a 77 K cold load in a standard Y factor measurement. The result is, depending on the receiver under study, an increase or decrease in the receiver noise temperature. We find that the small signal noise temperature, which is the noise temperature that would be observed without the presence of the direct detection effect, and thus the one that is relevant for an astronomical observation, is 20% lower than the noise temperature obtained using 300 K and 77 K calibration loads. Thus, in our case the direct detection effect reduces the mixer sensitivity. These results are in good agreement with previous measurement at THz frequencies [1]. Other experiments report an increase in mixer sensitivity [2]. To analyze this discrepancy we have designed a separate set of experiments to find out the physical origin of the direct detection effect. Possible candidates are the bias current dependence of the mixer gain and the bias current dependence of the IF match. We measured directly the change in mixer IF match and receiver gain due to the direct detection effect. From these measurements we conclude that the direct detection effect is caused by a combination of bias current reduction when switching form the 77 K to the 300 K load in combination with the bias current dependence of the receiver gain. The bias current dependence of the receiver gain is shown to be mainly caused by the current dependence of the mixer gain. We also find that an increase in receiver sensitivity due to the direct detection effect is only possible if the noise temperature change due to the direct detection is dominated by the mixer-amplifier IF match. [1] J.J.A. Baselmans, A. Baryshev, S.F. Reker, M. Hajenius, J.R. Gao, T.M. Klapwijk, Yu.Vachtomin, S. Maslennikov, S. Antipov, B. Voronov, and G. Gol'tsman., Appl. Phys. Lett. 86, 163503 (2005). [2] S. Svechnokov, A. Verevkin, B. Voronov, E. Menschikov. E. Gershenzon, G. Gol'tsman, 9th Int. Symp. On Space THz. Techn., 45, (1999). |
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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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Conference Article |
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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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