Records |
Author |
Ekström, H.; Kroug, M.; Belitsky, V.; Kollberg, E.; Olsson, H.; Goltsman, G.; Gershenzon, E.; Yagoubov, P.; Voronov, B.; Yngvesson, S. |
Title |
Hot electron mixers for THz applications |
Type |
Conference Article |
Year |
1996 |
Publication |
Proc. 30th ESLAB |
Abbreviated Journal |
Proc. 30th ESLAB |
Volume |
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Issue |
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Pages |
207-210 |
Keywords |
NbN HEB mixers |
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. |
Address |
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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Author |
Ekstörm, H.; Kollberg, E.; Yagoubov, P.; Gol'tsman, G.; Gershenzon, E.; Yngvesson, S. |
Title |
Gain and noise bandwidth of NbN hot-electron bolometric mixers |
Type |
Journal Article |
Year |
1997 |
Publication |
Appl. Phys. Lett. |
Abbreviated Journal |
Appl. Phys. Lett. |
Volume |
70 |
Issue |
24 |
Pages |
3296-3298 |
Keywords |
NbN HEB mixers, conversion loss, conversion gain, U-factor technique |
Abstract |
We have measured the noise performance and gain bandwidth of 35 Å thin NbN hot-electron mixers integrated with spiral antennas on silicon substrate lenses at 620 GHz. The best double-sideband receiver noise temperature is less than 1300 K with a 3 dB bandwidth of ≈5 GHz. The gain bandwidth is 3.2 GHz. The mixer output noise dominated by thermal fluctuations is 50 K, and the intrinsic conversion gain is about −12 dB. Without mismatch losses and excluding the loss from the beamsplitter, we expect to achieve a receiver noise temperature of less than 700 K. |
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no |
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Serial |
279 |
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Author |
Ekström, H.; Kollberg, E.; Yagoubov, P.; Gol'tsman, G.; Gershenzon, E.; Yngvesson, S. |
Title |
Phonon cooled ultra thin NbN hot electron bolometer mixers at 620 GHz |
Type |
Conference Article |
Year |
1997 |
Publication |
Proc. 8th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 8th Int. Symp. Space Terahertz Technol. |
Volume |
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Issue |
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Pages |
29-35 |
Keywords |
NbN HEB mixers |
Abstract |
We have measured the noise performance and gain bandwidth of 35 A thin NbN hot-electron mixers integrated with spiral antennas on silicon substrate lenses at 620 GHz. A double-sideband receiver noise temperature less than 1300 K has been obtained with a 3 dB bandwidth of GHz. The gain bandwidth is 3.2 GHz. A lower noise temperature of 1100 K has been achieved with an improved set-up. The mixer output noise dominated by thermal fluctuations is about 50-60 K, and the SSB receiver and intrinsic conversion gain is about -18 and -12 dB, respectively. Without mismatch losses and excluding the loss from the beamsplitter, we expect to achieve a receiver noise temperature of less than 700 K. |
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1604 |
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Author |
Ryabchun, S.; Tong, C.-Y. E.; Blundell, R.; Kimberk, R.; Gol'tsman, G. |
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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ISSN |
1051-8223 |
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no |
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Serial |
1427 |
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Author |
Huebers, H.-W.; Schubert, J.; Semenov, A.; Gol’tsman, G. N.; Voronov, B. M.; Gershenzon, E. M.; Schwaab, G. W. |
Title |
NbN phonon-cooled hot-electron bolometer as a mixer for THz heterodyne receivers |
Type |
Conference Article |
Year |
1999 |
Publication |
Proc. SPIE |
Abbreviated Journal |
Proc. SPIE |
Volume |
3828 |
Issue |
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Pages |
410-416 |
Keywords |
NbN HEB mixers |
Abstract |
We have investigated a phonon-cooled NbN hot electron bolometric (HEB) mixer in the frequency range from 0.7 THz to 5.2 THz. The device was a 3.5 nm thin film with an in- plane dimension of 1.7 X 0.2 micrometers 2 integrated in a complementary logarithmic spiral antenna. The measured DSB receiver noise temperatures are 1500 K, 2200 K, 2600 K, 2900 K, 4000 K, 5600 K and 8800 K. The sensitivity fluctuation, the long term stability, and the antenna pattern were measured and the suitability of the mixer for a practical heterodyne receiver is discussed. |
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Spie |
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Editor |
Chamberlain, J.M. |
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Conference |
Terahertz Spectroscopy and Applications II |
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no |
Call Number |
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Serial |
1477 |
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Author |
Tong, C. Edward; Trifonov, Andrey; Blundell, Raymond; Shurakov, Alexander; Gol’tsman, Gregory |
Title |
A digital terahertz power meter based on an NbN thin film |
Type |
Abstract |
Year |
2014 |
Publication |
Proc. 25th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 25th Int. Symp. Space Terahertz Technol. |
Volume |
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Issue |
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Pages |
170 |
Keywords |
waveguide NbN HEB mixers |
Abstract |
We have further studied the effect of subjecting a superconducting Hot Electron Bolometer (HEB) element made from an NbN thin film to microwave radiation. Since the photon energy is weak, the microwave radiation does not simply heat the film, but generates a bi-static state, switching between the superconducting and normal states, upon the application of a small voltage bias. Indeed, a relaxation oscillation of a few MHz has previously been reported in this regime [1]. Switching between the superconducting and normal states modulates the reflected microwave pump power from the device. A simple homodyne setup readily recovers the spontaneous switching waveform in the time domain. The switching frequency is a function of both the bias voltage (DC heating) and the applied microwave power. In this work, we use a 0.8 THz HEB waveguide mixer for the purpose of demonstration. The applied microwave pump, coupled through a directional coupler, is at 1 GHz. Since the pump power is of the order of a few μW, a room temperature amplifier is sufficient to amplify the reflected pump power from the HEB mixer, which beats with the microwave source in a homodyne set-up. After further amplification, the switching waveform is passed onto a frequency counter. The typical frequency of the switching pulses is 3-5 MHz. It is found that the digital frequency count increases with higher microwave pump power. When the HEB mixer is subjected to additional optical power at 0.8 THz, the frequency count also increases. When we vary the incident optical power by using a wire grid attenuator, a linear relationship is observed between the frequency count and the applied optical power, over at least an order of magnitude of power. This phenomenon can be exploited to develop a digital power meter, using a very simple electronics setup. Further experiments are under way to determine the range of linearity and the accuracy of calibration transfer from the microwave to the THz regime. References 1. Y. Zhuang, and S. Yngvesson, “Detection and interpretation of bistatic effects in NbN HEB devices,” Proc. 13 th Int. Symp. Space THz Tech., 2002, pp. 463–472. |
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Serial |
1366 |
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Author |
Yngvesson, K. S.; Gerecht, E.; Musante, C. F.; Zhuang, Y.; Ji, M.; Goyette, T. M.; Dickinson, J. C.; Waldman, J.; Yagoubov, P. A.; Gol’tsman, G. N.; Voronov, B. M.; Gershenzon, E. M. |
Title |
Low-noise HEB heterodyne receivers and focal plane arrays for the THz regime using NbN |
Type |
Conference Article |
Year |
1999 |
Publication |
Proc. SPIE |
Abbreviated Journal |
Proc. SPIE |
Volume |
3795 |
Issue |
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Pages |
357-368 |
Keywords |
NbN HEB mixers |
Abstract |
We have developed prototype HEB receivers using thin film superconducting NbN devices deposited on silicon substrates. The devices are quasi-optically coupled through a silicon lens and a self-complementary log-specific toothed antenna. We measured DSB receiver noise temperatures of 500 K (13 X hf/2k) at 1.56 THz and 1,100 K (20 X hf/2k) at 2.24 THz. Noise temperatures are expected to fall further as devices and quasi-optical coupling methods are being optimized. The measured 3 dB IF conversion gain bandwidth for one device was 3 GHz, and it is estimated that the bandwidth over which the receiver noise temperature is within 3 dB of its minimum value is 6.5 GHz which is sufficient for a number of practical applications. We will discuss our latest results and give a detailed description of our prototype setup and experiments. We will also discuss our plans for developing focal plane arrays with tens of Hot Electron Bolometric mixer elements on a single silicon substrate which will make real time imaging systems in the THz region feasible. |
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SPIE |
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Editor |
Hwu, R.J.; Wu, K. |
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Conference |
Terahertz and Gigahertz Photonics |
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no |
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Serial |
1561 |
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Author |
Meledin, D.; Tong, C. Y.-E.; Blundell, R.; Kaurova, N.; Smirnov, K.; Voronov, B.; Gol'tsman, G. |
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 |
Proc. 13th Int. Symp. Space Terahertz Technol. |
Volume |
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Issue |
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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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Cambridge, MA, USA |
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Harvard university |
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no |
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326 |
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Author |
Meledin, D.; Tong, C.-Y. E.; Blundell, R.; Goltsman, G. |
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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1531-1309 |
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1509 |
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Kawamura, J.; Tong, C.-Y. E.; Blundell, R.; Papa, D. C.; Hunter, T. R.; Patt, F.; Gol’tsman, G.; Gershenzon, E. |
Title |
Terahertz-frequency waveguide NbN hot-electron bolometer mixer |
Type |
Journal Article |
Year |
2001 |
Publication |
IEEE Trans. Appl. Supercond. |
Abbreviated Journal |
IEEE Trans. Appl. Supercond. |
Volume |
11 |
Issue |
1 |
Pages |
952-954 |
Keywords |
NbN HEB mixers |
Abstract |
We have developed a low-noise waveguide heterodyne receiver for operation near 1 THz using phonon-cooled NbN hot-electron bolometers. The mixer elements are submicron-sized microbridges of 4 nm-thick NbN film fabricated on a quartz substrate. Operating at a bath temperature of 4.2 K, the double-sideband receiver noise temperature is 760 K at 1.02 THz and 1100 K at 1.26 THz. The local oscillator is provided by solid-state sources, and power measured at the source is less than 1 /spl mu/W. The intermediate frequency bandwidth exceeds 2 GHz. The receiver was used to make the first ground-based heterodyne detection of a celestial spectroscopic line above 1 THz. |
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1558-2515 |
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1546 |
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Tong, C.-Y. E.; Meledin, D.; Loudkov, D.; Blundell, R.; Erickson, N.; Kawamura, J.; Mehdi, I.; Gol’tsman, G. |
Title |
A 1.5 THz Hot-Electron Bolometer mixer operated by a planar diode based local oscillator |
Type |
Conference Article |
Year |
2003 |
Publication |
IEEE MTT-S Int. Microwave Symp. Digest |
Abbreviated Journal |
IEEE MTT-S Int. Microwave Symp. Digest |
Volume |
2 |
Issue |
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Pages |
751-754 |
Keywords |
waveguide NbN HEB mixers |
Abstract |
We have developed a 1.5 THz superconducting NbN Hot-Electron Bolometer mixer. It is operated by an all-solid-state Local Oscillator comprising of a cascade of 4 planar doublers following an MMIC based W-band power amplifier. The threshold available pump power is estimated to be 1 /spl mu/W. |
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Philadelphia, PA, USA |
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1516 |
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Author |
Finkel, Matvey; Vachtomin, Yuriy; Antipov, Sereey; Drakinski, Vladimir; Kaurova, Natalia; Voronov, Boris; Goltsman, Greeory |
Title |
Gain bandwidth and noise temperature of NbTiN HEB mixer |
Type |
Conference Article |
Year |
2003 |
Publication |
Proc. 14th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 14th Int. Symp. Space Terahertz Technol. |
Volume |
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Issue |
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Pages |
276-285 |
Keywords |
NbTiN HEB mixer |
Abstract |
We have determined that the gain bandwidth of phonon-cooled HEB mixer employing NbTiN films deposited on MgO layer over Si substrate is limited b y the escape of phonons to the substrate. The cut-off frequencies of 1 um long devices operating at T 71, based on 3.5 nm. 4 nm and 10 nm thick films amount to 400 Mk. 300 MHz, and 100 MHz, respectivel y . The gain bandwidth of 0.13 . um long devices fabricated from 3.5 nm thick film is larger and amounts to 0.8 GIL; at the optimal operating point and to 1.5 GIL: at larger bias. The increase of the gain bandwidth from 400 MHz up to 1.5 GH: with the change of bridge length is attributed to diffusion cooling. A double sideband noise temperature of 4000 K was obtained for heterodyne receiver utilizing pilot NbTiN HEB mixer (not optimized for normal state resistance) operating at the local oscillator frequency of 2.5 THz. |
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1500 |
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Loudkov, D.; Tong, C.-Y.E.; Blundell, R.; Kaurova, N.; Grishina, E.; Voronov, B.; Gol’tsman, G. |
Title |
An investigation of the performance of the waveguide superconducting HEB mixer at different RF embedding impedances |
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Conference Article |
Year |
2005 |
Publication |
Proc. 16th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 16th Int. Symp. Space Terahertz Technol. |
Volume |
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Issue |
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Pages |
226-229 |
Keywords |
waveguide NbN HEB mixers |
Abstract |
We have conducted an investigation of the performance of superconducting hot-electron bolometric (HEB) mixer at 800 GHz as a function of the embedding impedance of the waveguide embedding circuit. Using a single half-height mixer block, we have developed three different mixer chip configurations, offering nominal embedding resistances of 70, 35, and 15 Ohms. Both the High Frequency Structure Simulator (HFSS) software and scaled model impedance measurements were employed in the design process. Two batches of HEB mixers were fabricated to these designs using 3-4 nm thick NbN thin film. The mixers were characterized through receiver noise temperature measurements and Fourier Transform Spectrometer (FTS) scans. Briefly, a minimum receiver noise temperature of 440 K was measured at a local oscillator frequency 850 GHz for a mixer of normal state resistance 62 Ohms incorporated into a circuit offering a nominal embedding impedance of 70 Ohms. We conclude from our data that, for low noise operation, the normal state resistance of the HEB mixer element should be close to that of the embedding impedance of the mixer mount. |
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Serial |
1472 |
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Author |
Loudkov, D.; Tong, C.-Y. E.; Blundell, R.; Kaurova, N.; Grishina, E.; Voronov, B.; Gol’tsman, G. |
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 |
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. |
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1439677 |
Serial |
1464 |
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Author |
Yang, Z. Q.; Hajenius, M.; Baselmans, J. J. A.; Gao, J. R.; Voronov, B.; Gol’tsman, G. N. |
Title |
Reduced noise in NbN hot-electron bolometer mixers by annealing |
Type |
Journal Article |
Year |
2006 |
Publication |
Supercond. Sci. Technol. |
Abbreviated Journal |
Supercond. Sci. Technol. |
Volume |
19 |
Issue |
4 |
Pages |
L (9 to 12) |
Keywords |
NbN HEB mixers |
Abstract |
We find that the sensitivity of heterodyne receivers based on superconducting hot-electron bolometers (HEBs) increases by 25–30% after annealing at 85 °C in vacuum. The devices studied are twin-slot antenna coupled mixers with a small NbN bridge of 1 × 0.15 µm2. We show that annealing changes the device properties as reflected in sharper resistive transitions of the complete device, apparently reducing the device-related noise. The lowest receiver noise temperature of 700 K is measured at a local oscillator frequency of 1.63 THz and a bath temperature of 4.3 K. |
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ISSN |
0953-2048 |
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no |
Call Number |
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Serial |
1456 |
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