| Records |
Author  |
Yagoubov, P.; Kroug, M.; Merkel, H.; Kollberg, E.; Gol'tsman, G.; Svechnikov, S.; Gershenzon, E. |
| Title |
Noise temperature and local oscillator power requirement of NbN phonon-cooled hot electron bolometric mixers at terahertz frequencies |
Type |
Journal Article |
| Year |
1998 |
Publication |
Appl. Phys. Lett. |
Abbreviated Journal |
Appl. Phys. Lett. |
| Volume |
73 |
Issue |
19 |
Pages |
2814-2816 |
| Keywords |
NbN HEB mixers, noise temperature, local oscillator power |
| Abstract |
In this letter, the noise performance of NbN-based phonon-cooled hot electron bolometric quasioptical mixers is investigated in the 0.55–1.1 THz frequency range. The best results of the double-sideband <cd><2018>DSB<cd><2019> noise temperature are: 500 K at 640 GHz, 600 K at 750 GHz, 850 K at 910 GHz, and 1250 K at 1.1 THz. The water vapor in the signal path causes significant contribution to the measured receiver noise temperature around 1.1 THz. The devices are made from 3-nm-thick NbN film on high-resistivity Si and integrated with a planar spiral antenna on the same substrate. The in-plane dimensions of the bolometer strip are typically 0.2Ï«2 um. The amount of local oscillator power absorbed in the bolometer is less than 100 nW. |
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911 |
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Yagoubov, P.; Gol'tsman, G.; Voronov, B.; Svechnikov, S.; Cherednichenko, S.; Gershenzon, E.; Belitsky, V.; Ekström, H.; Semenov, A.; Gousev, Yu.; Renk, K. |
| Title |
Quasioptical phonon-cooled NbN hot-electron bolometer mixer at THz frequencies |
Type |
Conference Article |
| Year |
1996 |
Publication |
Proc. 7th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 7th Int. Symp. Space Terahertz Technol. |
| Volume |
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Issue |
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Pages |
303-317 |
| Keywords |
NbN HEB mixers |
| Abstract |
In our experiments we tested phonon-cooled hot-electron bolometer (HEB) quasioptical mixer based on spiral antenna designed for 0.5-1.2 THz frequency band and fabricated on sapphire, Si-coated sapphire and high resistivity silicon substrates. HEB devices were produced from thin superconducting NbN film 3.5-6 nm thick with the critical temperature of about 11-12 K. For these devices we achieved the receiver noise temperature T R (DSB) = 3000 K in the 500-700 GHz frequency range and an IF bandwidth of 3-4 GHz. Prelimanary measurements at frequencies 1-1.2 THz resulted the receiver noise temperature about 9000 K (DSB). |
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1614 |
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Vakhtomin, Y. B.; Finkel, M. I.; Antipov, S. V.; Smirnov, K. V.; Kaurova, N. S.; Drakinskii, V. N.; Voronov, B. M.; Gol’tsman, G. N. |
| Title |
The gain bandwidth of mixers based on the electron heating effect in an ultrathin NbN film on a Si substrate with a buffer MgO layer |
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Journal Article |
| Year |
2003 |
Publication |
J. of communications technol. & electronics |
Abbreviated Journal |
J. of communications technol. & electronics |
| Volume |
48 |
Issue |
6 |
Pages |
671-675 |
| Keywords |
NbN HEB mixers |
| Abstract |
Measurements of the intermediate frequency band 900 GHz of mixers based on the electron heating effect (EHE) in 2-nm- and 3.5-nm-thick superconducting NbN films sputtered on MgO and Si substrates with buffer MgO layers are presented. A 2-nm-thick superconducting NbN film with a critical temperature of 9.2 K has been obtained for the first time using a buffer MgO layer. |
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MAIK Nauka/Interperiodica, Birmingham, AL |
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1064-2269 |
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https://elibrary.ru/item.asp?id=17302119 (Полоса преобразования смесителей на эффекте разогрева электронов в ультратонких пленках NbN на подложках из Si с подслоем MgO) |
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Vakhtomin2003 |
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1522 |
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Vahtomin, Yuriy B.; Finkel, Matvey I.; Antipov, Sergey V.; Voronov, Boris M.; Smirnov, Konstantin V.; Kaurova, Natalia S.; Drakinski, Vladimir N.; Gol'tsman, Gregogy N. |
| Title |
Gain bandwidth of phonon-cooled HEB mixer made of NbN thin film with MgO buffer layer on Si |
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Conference Article |
| Year |
2002 |
Publication |
Proc. 13th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 13th Int. Symp. Space Terahertz Technol. |
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Issue |
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Pages |
259-270 |
| Keywords |
NbN HEB mixers, conversion gain bandwidth |
| Abstract |
We present recently obtained values for gain bandwidth of NbN HEB mixers for different substrates and film thicknesses and for MgO buffer layer on Si at LO frequency of 0.85-1 THz. The maximal bandwidth, 5.2 GHz, was achieved for the device on MgO buffer layer on Si with a 2 nm thick NbN film. Functional devices based on NbN films of such thickness were fabricated for the first time due to an improvement of superconducting properties of NbN film deposited on MgO buffer layer on Si substrate. |
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Cambridge, MA, USA |
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Harvard university |
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no |
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325 |
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Vachtomin, Y. B.; Antipov, S. V.; Maslennikov, S. N.; Smirnov, K. V.; Polyakov, S. L.; Zhang, W.; Svechnikov, S. I.; Kaurova, N. S.; Grishina, E. V.; Voronov, B. M.; Gol’tsman, G. N. |
| Title |
Quasioptical hot electron bolometer mixers based on thin NBN films for terahertz region |
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Conference Article |
| Year |
2006 |
Publication |
Proc. 16th Int. Crimean Microwave and Telecommunication Technology |
Abbreviated Journal |
Proc. 16th Int. Crimean Microwave and Telecommunication Technology |
| Volume |
2 |
Issue |
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Pages |
688-689 |
| Keywords |
NbN HEB mixers |
| Abstract |
Presented in this paper are the performances of HEB mixers based on 2-3.5 nm thick NbN films integrated with log-periodic spiral antenna. Double side-band receiver noise temperature values are 1300 K and 3100 K at 2.5 THz and at 3.8 THz, respectively. Mixer gain bandwidth is 5.2 GHz. Local oscillator power is 1-3 muW for mixers with different active area |
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Russian |
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no |
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1445 |
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Trifonov, A.; Tong, C.-Y. E.; Lobanov, Y.; Kaurova, N.; Blundell, R.; Goltsman, G. |
| Title |
Photon absorption near the gap frequency in a hot electron bolometer |
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Journal Article |
| Year |
2017 |
Publication |
IEEE Trans. Appl. Supercond. |
Abbreviated Journal |
IEEE Trans. Appl. Supercond. |
| Volume |
27 |
Issue |
4 |
Pages |
1-4 |
| Keywords |
NBN HEB mixer |
| Abstract |
The superconducting energy gap is a fundamental characteristic of a superconducting film, which, together with the applied pump power and the biasing setup, defines the instantaneous resistive state of the Hot Electron Bolometer (HEB) mixer at any given bias point on the I-V curve. In this paper we report on a series of experiments, in which we subjected the HEB to radiation over a wide frequency range along with parallel microwave injection. We have observed three distinct regimes of operation of the HEB, depending on whether the radiation is above the gap frequency, far below it or close to it. These regimes are driven by the different patterns of photon absorption. The experiments have allowed us to derive the approximate gap frequency of the device under test as about 585 GHz. Microwave injection was used to probe the HEB impedance. Spontaneous switching between the superconducting (low resistive) state and a quasi-normal (high resistive) state was observed. The switching pattern depends on the particular regime of HEB operation and can assume a random pattern at pump frequencies below the gap to a regular relaxation oscillation running at a few MHz when pumped above the gap. |
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1558-2515 |
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no |
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1331 |
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| Author |
Trifonov, A.; Tong, C.-Y. E.; Blundell, R.; Ryabchun, S.; Gol'tsman, G. |
| Title |
Probing the stability of HEB mixers with microwave injection |
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Journal Article |
| Year |
2015 |
Publication |
IEEE Trans. Appl. Supercond. |
Abbreviated Journal |
IEEE Trans. Appl. Supercond. |
| Volume |
25 |
Issue |
3 |
Pages |
2300404 (1 to 4) |
| Keywords |
NbN HEB mixer, stability, Allan-variance |
| Abstract |
Using a microwave probe as a tool, we have performed experiments aimed at understanding the origin of the output-power fluctuations in hot-electron-bolometer (HEB) mixers. We use a probe frequency of 1.5 GHz. The microwave probe picks up impedance changes of the HEB, which are examined upon demodulation of the reflected wave outside the cryostat. This study shows that the HEB mixer operates in two different regimes under a terahertz pump. At a low pumping level, strong pulse modulation is observed, as the device switches between the superconducting state and the normal state at a rate of a few megahertz. When pumped much harder, to approximate the low-noise mixer operating point, residual modulation can still be observed, showing that the HEB mixer is intrinsically unstable even in the resistive state. Based on these observations, we introduced a low-frequency termination to the HEB mixer. By terminating the device in a 50-Ω resistor in the megahertz frequency range, we have been able to improve the output-power Allan time of our HEB receiver by a factor of four to about 10 s for a detection bandwidth of 15 MHz, with a corresponding gain fluctuation of about 0.035%. |
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1051-8223 |
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no |
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1355 |
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Tret’yakov, I. V.; Ryabchun, S. A.; Kaurova, N. S.; Larionov, P. A.; Lobastova, A. A.; Voronov, B. M.; Finkel, M. I.; Gol’tsman, G. N. |
| Title |
Optimum absorbed heterodyne power for superconducting NbN hot-electron bolometer mixer |
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Journal Article |
| Year |
2010 |
Publication |
Tech. Phys. Lett. |
Abbreviated Journal |
Tech. Phys. Lett. |
| Volume |
36 |
Issue |
12 |
Pages |
1103-1105 |
| Keywords |
NbN HEB mixer |
| Abstract |
Absorbed heterodyne power has been measured in a low-noise broadband hot-electron bolometer (HEB) mixer for the terahertz range, operating on the effect of electron heating in the resistive state of an ultrathin superconducting NbN film. It is established that the optimum absorbed heterodyne power for the HEB mixer operating at 2.5 THz is about 100 nW. |
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1063-7850 |
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no |
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1389 |
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Tretyakov, Ivan; Seliverstov, Sergey; Zolotov, Philipp; Kaurova, Natalya; Voronov, Boris; Finkel, Matvey; Goltsman, Gregory |
| Title |
Noise temperature and noise bandwidth of hot-electron bolometer mixer at 3.8 THz |
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Abstract |
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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 |
77 |
| Keywords |
NbN HEB mixer |
| Abstract |
We report on our recent results of double sideband (DSB) noise temperature and bandwidth measurements of quasi-optical hot electron bolometer (HEB) mixers at local oscillator frequency of 3.8 THz. The HEB mixers used in this work were made of a NbN thin film and had a superconducting transition temperature of about 10.3 K. To couple terahertz radiation, the NbN microbridge (0.2 μm long and 2 μm wide) was integrated with a planar logarithmic-spiral antenna. The mixer chip was glued to an elliptical Si lens clamped tightly to a mixer block mounted on the 4.2 K plate of a liquid helium cryostat. The terahertz radiation was fed into the HEB device through the cryostat window made of a 0.5 mm thick HDPE. A band-pass mesh filter was mounted on the 4.2 K plate to minimize the direct detection effect [1]. We used a gas discharge laser irradiating at 3.8 THz H 2 0 line as a local oscillator (LO). The LO power was combined with a black body broadband radiation via Mylar beam splitter. Our receiver allows heterodyne detection with an intermediate frequency (IF) of a several gigahertz which dictates usage of a wideband SiGe low noise amplifier [2]. The receiver IF output signal was further amplified at room temperature and fed into a square-law power detector through a band-pass filter. The DSB receiver noise temperature was measured using a conventional Y-factor technique at IF of 1.25 GHz and band of 40 MHz. Using wideband amplifiers at both cryogenic and room temperature stages we have estimated IF bandwidth of the HEB mixers used. The obtained results strengthen the position of the HEB mixer as one of the most important tools for submillimeter astronomy. This device operates well above the energy gap (at frequencies above 1 THz) where performance of state-of-the-art SIS mixers starts to degrade. So, HEB mixers are expected to be a device of choice in astrophysical observations (ground-, aircraft- and space-based) at THz frequencies due to its excellent noise performance and low LO power requirements. The HEB mixers will be in operation on Millimetron Space Observatory. References 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. Sander Weinreb, Life Fellow, IEEE, Joseph C. Bardin, Student Member, IEEE, and Hamdi Mani, “Design of Cryogenic SiGe Low-Noise Amplifiers”, IEEE Transactions on Microwave Theory and Techniques, 55, 11, 2007. |
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1362 |
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Tretyakov, Ivan; Ryabchun, Sergey; Finkel, Matvey; Maslennikova, Anna; Kaurova, Natalia; Lobastova, Anastasia; Voronov, Boris; Gol'tsman, Gregory |
| Title |
Low noise and wide bandwidth of NbN hot-electron bolometer mixers |
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Journal Article |
| Year |
2011 |
Publication |
Appl. Phys. Lett. |
Abbreviated Journal |
Appl. Phys. Lett. |
| Volume |
98 |
Issue |
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Pages |
033507 (1 to 3) |
| Keywords |
NbN HEB mixer |
| Abstract |
We report a record double sideband noise temperature of 600 K (5hν/kB) offered by a NbN hot-electron bolometer receiver at 2.5 THz. Allowing for standing wave effects, this value was found to be constant in the intermediate frequency range 1–7 GHz, which indicates that the mixer has an unprecedentedly large noise bandwidth in excess of 7 GHz. The insight into this is provided by gain bandwidth measurements performed at the superconducting transition. They show that the dependence of the bandwidth on the mixer length follows the model for an HEB mixer with diffusion and phonon cooling of the hot electrons. |
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RPLAB @ gujma @ |
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638 |
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Tretyakov, Ivan; Ryabchun, Sergey; Finkel, Matvey; Maslennikov, Sergey; Maslennikova, Anna; Kaurova, Natalia; Lobastova, Anastasia; Voronov, Boris; Gol'tsman, Gregory |
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Ultrawide noise bandwidth of NbN hot-electron bolometer mixers with in situ gold contacts |
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Journal Article |
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2011 |
Publication |
IEEE Trans. Appl. Supercond. |
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| Volume |
21 |
Issue |
3 |
Pages |
620-623 |
| Keywords |
NbN HEB mixer bandwidth |
| Abstract |
We report a noise bandwidth of 7 GHz in the new generation of NbN hot-electron bolometer (HEB) mixers that are being developed for the space observatory Millimetron. The HEB receiver driven by a 2.5-THz local oscillator offered a noise temperature of 600 K in a 50-MHz final detection bandwidth. As the filter center frequency was swept this value remained nearly constant up to the cutoff frequency of the cryogenic amplifier at 7 GHz. We believe that such a low value of the noise temperature is due to reduced radio frequency (RF) loss at the interface between the superconducting film and the gold contacts. We have also performed gain bandwidth measurements at the superconducting transition on HEB mixers with various lengths and found them to be in excellent agreement with the results of the analytical and numerical models developed for the HEB mixer with both diffusion and phonon cooling of hot electrons. |
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RPLAB @ gujma @ |
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716 |
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Tretyakov, Ivan; Kaurova, N.; Voronov, B. M.; Goltsman, G. N. |
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About effect of the temperature operating conditions on the noise temperature and noise bandwidth of the terahertz range NbN hot-electron bolometers |
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Abstract |
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2018 |
Publication |
Proc. 29th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 29th Int. Symp. Space Terahertz Technol. |
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Issue |
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Pages |
113 |
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NbN HEB mixer |
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Results of an experimental study of the noise temperature (Tn) and noise bandwidth (NBW) of the superconductor NbN hot-electron bolometer (HEB) mixer as a function of its temperature (Tb) and NbN bridge length are presented. It was determined that the NBW of the mixer is significantly wider at temperatures close to the critical ones (Tc) than are values measured at 4.2 K. The NBW of the mixer measured at the heterodyne frequency of 2.5 THz at temperature Tb close to Tc was ~13 GHz, as compared with 6 GHz at Tb = 4.2 K. This experiment clearly demonstrates the limitation of the thermal flow from the NbN bridge at Tb ≪ Tc for mixers manufactured by the in situ technique. This limitation is close in its nature to the Andreev reflection on the superconductor/metal boundary. In this case, the noise temperature of the studied mixer increased from 1100 to 3800 K. |
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1313 |
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Tretyakov, I.; Maslennikov, S.; Semenov, A.; Safir, O.; Finkel, M.; Ryabchun, S.; Kaurova, N.; Voronov, B.; Goltsman, G.; Klapwijk, T. M. |
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Impact of operating conditions on noise and gain bandwidth of NbN HEB mixers |
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Conference Article |
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2015 |
Publication |
Proc. 26th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 26th Int. Symp. Space Terahertz Technol. |
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39 |
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NbN HEB mixers |
| Abstract |
Hot-electron bolometer mixers (HEB’s) are the most promising devices as mixing element for terahertz spectroscopy and astronomy at frequencies beyond 1.4 THz. They have a low noise temperature and low demands on local oscillator (LO) power. 1,2 An important limitation is the IF bandwidth, of the order of a few GHz, and which in principle depends on energy relaxation due to electron- phonon processes and on diffusion-cooling. It has been proposed by Prober that a reduction in length of the HEB would lead to an increased bandwidth. 3 This appeared to be achieved by Tretyakov et al by measuring the gain bandwidth close to the critical temperature of the NbN. 2 Unfortunately, the noise bandwidth of similar devices operated at temperatures around 4.2 K appear not depend on the length. The fundamental problem to be addressed is the position-dependent superconducting state of the HEB- devices under operating conditions, which determines the conditions for the cooling of the hot quasiparticles. Some progress has been made by Barends et al in a semi-empirical model to describe the I,V curves under operating conditions at a bath temperature around 4.2 K. 4 In more recent work Vercruyssen et al have analyzed the I,V curve, without any LO-equivalent bias, of a model NSN system. 5 This work suggests that the most appropriate model for an HEB under operating conditions is that of a potential-well in the superconducting gap in the center of the NbN, analogous the bimodal superconducting state described by Vercruyssen et al. Hot quasiparticles in the well can not diffuse out and can only cool by electron-phonon processes, those with higher energies than the heights of the walls of the well can diffuse out. Using this working hypothesis we have carried out experiments on a sub-micrometer NbN bridge connected to a gold (Au) planar spiral antenna. An in situ process is used to deposit Au on NbN. The Au is removed in the center to define the uncovered NbN, which will act as the superconducting mixer itself. The antenna is deposited on the remaining Au layer on the NbN. The Au contacts suppress the energy gap of the NbN film located underneath the gold layer 7,8 . The measured resistive transition is shown in Fig.1. It clearly shows a T c of the bilayer at 6.2 K and the resistive transition of the NbN itself around 9 K. In addition we show the measured noise bandwidth (red squares) for different bath temperatures. Clearly the noise bandwidth increases strongly by increasing the bath temperature from 5 K to 8 K, up to 13 GHz. We interpret this pattern as evidence for improved out-diffusion of hot electrons due to normal banks and a shallow superconducting potential well compared to k B T. As expected the noise temperature in this regime is much bigger than when biased at 4.2 K. R EFERENCES 1 W. Zhang, P. Khosropanah, J. R. Gao, E. L. Kollberg, K. S. Yngvesson, T. Bansal, R. Barends, and T. M. Klapwijk Appl. Phys. Lett. 96, 111113, (2010). 2 Ivan Tretyakov, Sergey Ryabchun, Matvey Finkel, Anna Maslennikova, Natalia Kaurova, Anastasia Lobastova, Boris Voronov, and Gregory Gol’tsman Appl. Phys. Lett. 98, 033507 (2011). 3 D. E. Prober, Appl. Phys. Lett. 62, 2119 (1992). 4 R. Barends, M. Hajenius, J. R. Gao, and T. M. Klapwijk, Appl. Phys. Lett. 87, 263506 (2005). 5 N. Vercruyssen, T. G. A. Verhagen, M. G. Flokstra, J. P. Pekola, and T. M. Klapwijk Physical Review B 85, 224503 (2012). |
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Tretyakov, I. V.; Anfertyev, V. A.; Revin, L. S.; Kaurova, N. S.; Voronov, B. M.; Vaks, V. L.; Goltsman, G. N. |
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Sensitivity and resolution of a heterodyne receiver based on the NbN HEB mixer with a quantum-cascade laser as a local oscillator |
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2018 |
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Radiophys. Quant. Electron. |
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Radiophys. Quant. Electron. |
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60 |
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12 |
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988-992 |
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NbN HEB mixer |
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We present the results of experimental studies of the basic characteristics and operation features of a terahertz heterodyne detector based on the superconducting NbN HEB mixer and a quantum cascade laser as a local oscillator operating at a frequency of 2.02 THz. The measured noise temperature of such a mixer amounted to 1500 K. The spectral resolution of the detector is determined by the width of the local-oscillator spectral line whose measured value does not exceed 1 MHz. The quantum-cascade laser could be linearly tuned with respect to frequency with the coefficient 7.2 MHz/mA within the limits of the current oscillation bandwidth. |
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0033-8443 |
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Tong, C.-Y. Edward; Meledin, Denis; Blundell, Raymond; Erickson, Neal; Kawamura, Jonathan; Mehdi, Imran; Gol'tsman, Gregory |
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A 1.5 THz hot-electron bolometer mixer operated by a planar diode-based local oscillator |
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2003 |
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Proc. 14th Int. Symp. Space Terahertz Technol. |
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Proc. 14th Int. Symp. Space Terahertz Technol. |
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286 |
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waveguide NbN HEB mixers |
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We describe a 1.5 THz heterodyne receiver based on a superconductin g hot-electron bolometer mixer, which is pumped by an all-solid-state local oscillator chain. The bolometer is fabricated from a 3.5 nm-thick niobium nitride film deposited on a quartz substrate with a 200 nm-thick magnesium oxide buffer layer. The bolometer measures 0.15 fun in width and 1.5 1..tm in length. The chip consisting of the bolometer and mixer circuitry is incorporated in a fixed-tuned waveguide mixer block with a corru g ated feed horn. The local oscillator unit comprises of a cascade of four planar doublers followin g a MMIC-based W-band power amplifier. The local oscillator is coupled to the mixer using a Martin-Puplett interferometer. The local oscillator output power needed for optimal receiver performance is approximately 1 to 2 11W, and the chain is able to provide this power at a number of frequency points between 1.45 and 1.56 THz. By terminating the rf input with room temperature and 77 K loads, a Y-factor of 1.11 (DSB) has been measured at a local oscillator frequency of 1.476 THz at 3 GHz intermediate frequency. |
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