| Records |
| Author |
Lobanov, Y.; Shcherbatenko, M.; Semenov, A.; Kovalyuk, V.; Kahl, O.; Ferrari, S.; Korneev, A.; Ozhegov, R.; Kaurova, N.; Voronov, B. M.; Pernice, W. H. P.; Gol'tsman, G. N. |
| Title |
Superconducting nanowire single photon detector for coherent detection of weak signals |
Type |
Journal Article |
| Year |
2017 |
Publication |
IEEE Trans. Appl. Supercond. |
Abbreviated Journal |
IEEE Trans. Appl. Supercond. |
| Volume |
27 |
Issue |
4 |
Pages  |
1-5 |
| Keywords |
NbN SSPD mixer, SNSPD, nanophotonic waveguide |
| Abstract |
Traditional photon detectors are operated in the direct detection mode, counting incident photons with a known quantum efficiency. Here, we have investigated a superconducting nanowire single photon detector (SNSPD) operated as a photon counting mixer at telecommunication wavelength around 1.5 μm. This regime of operation combines excellent sensitivity of a photon counting detector with excellent spectral resolution given by the heterodyne technique. Advantageously, we have found that low local oscillator (LO) power of the order of hundreds of femtowatts to a few picowatts is sufficient for clear observation of the incident test signal with the sensitivity approaching the quantum limit. With further optimization, the required LO power could be significantly reduced, which is promising for many practical applications, such as the development of receiver matrices or recording ultralow signals at a level of less-than-one-photon per second. In addition to a traditional NbN-based SNSPD operated with normal incidence coupling, we also use detectors with a travelling wave geometry, where a NbN nanowire is placed on the top of a Si 3 N 4 nanophotonic waveguide. This approach is fully scalable and a large number of devices could be integrated on a single chip. |
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1051-8223 |
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no |
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1206 |
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| Author |
Polyakova, M.; Semenov, A. V.; Kovalyuk, V.; Ferrari, S.; Pernice, W. H. P.; Gol'tsman, G. N. |
| Title |
Protocol of measuring hot-spot correlation length for SNSPDs with near-unity detection efficiency |
Type |
Journal Article |
| Year |
2019 |
Publication |
IEEE Trans. Appl. Supercond. |
Abbreviated Journal |
IEEE Trans. Appl. Supercond. |
| Volume |
29 |
Issue |
5 |
Pages |
1-5 |
| Keywords |
SSPD, waveguide-integrated SNSPD, hot-spot interaction length |
| Abstract |
We present a simple quantum detector tomography protocol, which allows, without ambiguities, to measure the two-spot detection efficiency and extract the hot-spot interaction length of superconducting nanowire single photon detectors (SNSPDs) with unity intrinsic detection efficiency. We identify a significant parasitic contribution to the measured two-spot efficiency, related to an effect of the bias circuit, and find a way to rule out this contribution during data post-processing and directly in the experiment. From the data analysis for waveguide-integrated SNSPD, we find signatures of the saturation of the two-spot efficiency and hot-spot interaction length of order of 100 nm. |
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1051-8223 |
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no |
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1187 |
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Zolotov, P. I.; Semenov, A. V.; Divochiy, A. V.; Goltsman, G. N.; Romanov, N. R.; Klapwijk, T. M. |
| Title |
Dependence of photon detection efficiency on normal-state sheet resistance in marginally superconducting films of NbN |
Type |
Journal Article |
| Year |
2021 |
Publication |
IEEE Trans. Appl. Supercond. |
Abbreviated Journal |
IEEE Trans. Appl. Supercond. |
| Volume |
31 |
Issue |
5 |
Pages |
1-5 |
| Keywords |
NbN SSPD, SNSPD |
| Abstract |
We present an extensive set of data on nanowire-type superconducting single-photon detectors based on niobium-nitride (NbN) to establish the empirical correlation between performance and the normal-state resistance per square. We focus, in particular, on the bias current, compared to the expected depairing current, needed to achieve a near-unity detection efficiency for photon detection. The data are discussed within the context of a model in which the photon energy triggers the movement of vortices i.e. superconducting dissipation, followed by thermal runaway. Since the model is based on the non-equilibrium theory for conventional superconductors deviations may occur, because the efficient regime is found when NbN acts as a marginal superconductor in which long-range phase coherence is frustrated. |
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1051-8223 |
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no |
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Serial |
1222 |
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Zolotov, P.; Semenov, A.; Divochiy, A.; Goltsman, G. |
| Title |
A comparison of VN and NbN thin films towards optimal SNSPD efficiency |
Type |
Journal Article |
| Year |
2021 |
Publication |
IEEE Trans. Appl. Supercond. |
Abbreviated Journal |
IEEE Trans. Appl. Supercond. |
| Volume |
31 |
Issue |
5 |
Pages |
1-4 |
| Keywords |
NbN SSPD, SNSPD, WSi |
| Abstract |
Based on early phenomenological ideas about the operation of superconducting single-photon detectors (SSPD or SNSPD), it was expected that materials with a lower superconducting gap should perform better in the IR range. The plausibility of this concept could be checked using two popular SSPD materials – NbN and WSi films. However, these materials differ strongly in crystallographic structure (polycrystalline B1 versus amorphous), which makes their dependence on disorder different. In our work we present a study of the single-photon response of SSPDs made from two disordered B1 structure superconductors – vanadium nitride and niobium nitride thin films. We compare the intrinsic efficiency of devices made from films with different sheet resistance values. While both materials have a polycrystalline structure and comparable diffusion coefficient values, VN films show metallic behavior over a wide range of sheet resistance, in contrast to NbN films with an insulator-like temperature dependence of resistivity, which may be partially due to enhanced Coulomb interaction, leading to different starting points for the normal electron density of states. The results show that even though VN devices are more promising in terms of theoretical predictions, their optimal performance was not reached due to lower values of sheet resistance. |
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1051-8223 |
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no |
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1223 |
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Saveskul, N. A.; Titova, N. A.; Baeva, E. M.; Semenov, A. V.; Lubenchenko, A. V.; Saha, S.; Reddy, H.; Bogdanov, S. I.; Marinero, E. E.; Shalaev, V. M.; Boltasseva, A.; Khrapai, V. S.; Kardakova, A. I.; Goltsman, G. N. |
| Title |
Superconductivity behavior in epitaxial TiN films points at surface magnetic disorder |
Type |
Miscellaneous |
| Year |
2019 |
Publication |
arXiv |
Abbreviated Journal |
arXiv |
| Volume |
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Issue |
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Pages |
1-10 |
| Keywords |
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| Abstract |
We analyze the evolution of the normal and superconducting electronic properties in epitaxial TiN films, characterized by high Ioffe-Regel parameter values, as a function of the film thickness. As the film thickness decreases, we observe an increase of in the residual resistivity, which becomes dominated by diffusive surface scattering for d≤20nm. At the same time, a substantial thickness-dependent reduction of the superconducting critical temperature is observed compared to the bulk TiN value. In such a high quality material films, this effect can be explained by a weak magnetic disorder residing in the surface layer with a characteristic magnetic defect density of ∼1012cm−2. Our results suggest that surface magnetic disorder is generally present in oxidized TiN films. |
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no |
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1278 |
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Korneev, A.; Korneeva, Y.; Florya, I.; Semenov, A.; Goltsman, G. |
| Title |
Photon switching statistics in multistrip superconducting single-photon detectors |
Type |
Journal Article |
| Year |
2018 |
Publication |
IEEE Trans. Appl. Supercond. |
Abbreviated Journal |
IEEE Trans. Appl. Supercond. |
| Volume |
28 |
Issue |
7 |
Pages |
1-4 |
| Keywords |
SSPD, SNSPD |
| Abstract |
We study photon count statistics in superconducting single-photon detectors consisting of up to 70 narrow superconducting strips connected in parallel. Using interarrival time analysis, we demonstrate that our samples are operated in the “arm-trigger” regime and require up to seven subsequently absorbed photons to form a resistive state in the whole sample. We also performed numerical simulation of the light and dark count rates versus detector bias current, which are in good agreement with the experimental results. |
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1051-8223 |
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no |
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1304 |
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Korneeva, Y.; Sidorova, M.; Semenov, A.; Krasnosvobodtsev, S.; Mitsen, K.; Korneev, A.; Chulkova, G.; Goltsman, G. |
| Title |
Comparison of hot-spot formation in NbC and NbN single-photon detectors |
Type |
Journal Article |
| Year |
2016 |
Publication |
IEEE Trans. Appl. Supercond. |
Abbreviated Journal |
IEEE Trans. Appl. Supercond. |
| Volume |
26 |
Issue |
3 |
Pages |
1-4 |
| Keywords |
NbC, NbN SSPD, SNSPD |
| Abstract |
We report an experimental investigation of the hot-spot evolution in superconducting single-photon detectors made of disordered superconducting materials with different diffusivity and energy downconversion time values, i.e., 33-nm-thick NbN and 23-nm-thick NbC films. We have demonstrated that, in NbC film, only 405-nm photons produce sufficiently large hot spot to trigger a single-photon response. The dependence of detection efficiency on bias current for 405-nm photons in NbC is similar to that for 3400-nm photons in NbN. In NbC, large diffusivity and downconversion time result in 1-D critical current suppression profile compared with the usual 2-D profile in NbN. |
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1051-8223 |
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no |
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1348 |
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Hübers, H.-W.; Semenov, A.; Richter, H.; Birk, M.; Krocka, M.; Mair, U.; Smirnov, K.; Gol’tsman, G.; Voronov, B. |
| Title |
Terahertz Heterodyn Receiver with a hot-electron bolometer mixer |
Type |
Conference Article |
| Year |
2002 |
Publication |
Far-IR, Sub-mm & MM Detector Technology Workshop |
Abbreviated Journal |
Far-IR, Sub-mm & MM Detector Technology Workshop |
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Issue |
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Pages |
3-24 |
| Keywords |
NbN HEB mixers |
| Abstract |
During the past decade major advances have been made regarding low noise mixers for terahertz (THz) heterodyne receivers. State of the art hot-electron-bolometer (HEB) mixers have noise temperatures close to the quantum limit and require less than a µW power from the local oscillator (LO). The technology is now at a point where the performance of a practical receiver employing such mixer, rather than the figures of merit of the mixer itself, are of major concern. We have incorporated a phonon-cooled NbN HEB mixer in a 2.5 THz heterodyne receiver and investigated the performance of the receiver. This yields important information for the development of heterodyne receivers such as GREAT (German receiver for astronomy at THz frequencies aboard SOFIA) [1] and TELIS (Terahertz limb sounder), a balloon borne heterodyne receiver for atmospheric research [2]. Both are currently under development at DLR. |
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NASA |
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Wolf, U.; Farhoomand, J.; McCreight, C.R. |
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NASA CP |
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Volume: 211408 |
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no |
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1537 |
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Semenov, A.; Hübers, H.-W.; Engel, A.; Gol’tsman, G. |
| Title |
Superconducting quantum detector for far infrared astronomy |
Type |
Conference Article |
| Year |
2002 |
Publication |
Far-IR, Sub-mm & MM Detector Technology Workshop |
Abbreviated Journal |
Far-IR, Sub-mm & MM Detector Technology Workshop |
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Issue |
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Pages |
3-49 |
| Keywords |
SQD |
| Abstract |
We present the concept of the superconducting quantum detector for astronomy. Response to a single absorbed photon appears due to successive formation of a normal spot and phase-slip-centres in a narrow strip carrying sub-critical supercurrent. The detector simultaneously has a moderate energy resolution and a variable cut-off wavelength depending on both the material used and operation conditions. We simulated performance of the background-limited direct detector having the 100-micrometer cut-off wavelength. Low dark count rate will allow to realise 10-21 W Hz-1/2 noise equivalent power at 4 K background radiation. The detection mechanism provides a moderate 1/20 energy resolution at 50-micrometer wavelength. |
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NASA |
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Wolf, J.; Farhoomand, J.; McCreight, C.R. |
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NASA CP |
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Volume: 211408 |
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no |
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1538 |
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Gershenzon, E. M.; Gogidze, I. G.; Goltsman, G. N.; Semenov, A. D.; Sergeev, A. V. |
| Title |
Picosecond response on optical-range emission in thin YBaCuO films |
Type |
Journal Article |
| Year |
1991 |
Publication |
Pisma v Zhurnal Tekhnicheskoi Fiziki |
Abbreviated Journal |
Pisma v Zhurnal Tekhnicheskoi Fiziki |
| Volume |
17 |
Issue |
22 |
Pages |
6-10 |
| Keywords |
YBCO HTS detectors |
| Abstract |
Целью настоящей работы является целенаправленный поиск пико-секундного отклика на оптическое излучение выяснение оптимальных условий его наблюдения, а также сравнение характеристик неравновесных эффектов в оптическом и субмиллиметровом диапазонах. |
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Russian |
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1684 |
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Gershenzon, E. M.; Gershenson, M. E.; Goltsman, G. N.; Lyulkin, A. M.; Semenov, A. D.; Sergeev, A. V. |
| Title |
Limiting characteristics of fast-response superconducting bolometers |
Type |
Journal Article |
| Year |
1989 |
Publication |
Zhurnal Tekhnicheskoi Fiziki |
Abbreviated Journal |
Zhurnal Tekhnicheskoi Fiziki |
| Volume |
59 |
Issue |
2 |
Pages |
11-120 |
| Keywords |
HEB |
| Abstract |
Теоретически и экспериментально исследовано физическое ограничение быстродействия сверхпроводящего болометра. Показано, что минимальная постоянная времени реализуется в условиях электронного разогрева и определяется процессом неупругого электрон-фонон-ного взаимодействия. Сформулированы требования к конструкции «электронного болометра» для достижения предельной чувствительности. Проведено сравнение характеристик электронного болометра и обычных болометров различных типов. |
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no |
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1696 |
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Hübers, H. W.; Pavlov, S. G.; Semenov, A. D.; Tredicucci, A.; Köhler, R.; Mahler, L.; Beere, H. E.; Linfield, E. H.; Ritchie, D. A. |
| Title |
Investigation of a 2.5 THz quantum cascade laser as local oscillator |
Type |
Conference Article |
| Year |
2005 |
Publication |
Proc. 16th Int. Symp. Space Terahertz Technol. |
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Pages |
18 |
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Göteborg, Sweden |
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RPLAB @ s @ qc_lasers_huebers |
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366 |
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Semenov, A. D.; Hübers, H.–W.; Schubert, J.; Gol'tsman, G. N.; Elantiev, A. I.; Voronov, B. M.; Gershenzon, E. M. |
| Title |
Frequency dependent noise temperature of the lattice cooled hot-electron terahertz mixer |
Type |
Conference Article |
| Year |
2000 |
Publication |
Proc. 11th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 11th Int. Symp. Space Terahertz Technol. |
| Volume |
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Issue |
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Pages |
39-48 |
| Keywords |
NbN HEB mixers |
| Abstract |
We present the measurements and the theoretical model on the frequency dependent noise temperature of a lattice cooled hot electron bolometer (HEB) mixer in the terahertz frequency range. The experimentally observed increase of the noise temperature with frequency is a cumulative effect of the non-uniform distribution of the high frequency current in the bolometer and the charge imbalance, which occurs near the edges of the normal domain and contacts with normal metal. In addition, we present experimental results which show that the noise temperature of a HEB mixer can be reduced by about 30% due to a Parylene antireflection coating on the Silicon hyperhemispheric lens. |
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305 |
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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. |
| Title |
Impact of operating conditions on noise and gain bandwidth of NbN HEB mixers |
Type |
Conference Article |
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2015 |
Publication |
Proc. 26th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 26th Int. Symp. Space Terahertz Technol. |
| Volume |
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Issue |
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Pages |
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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Hübers, H.-W.; Schubert, J.; Krabbe, A.; Birk, M.; Wagner, G.; Semenov, A.; Gol’tsman, G.; Voronov, B.; Gershenzon, E. |
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Parylene anti-reflection coating of a quasi-optical hot-electron-bolometric mixer at terahertz frequencies |
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2001 |
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Infrared Physics & Technology |
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Infrared Physics & Technology |
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42 |
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1 |
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41-47 |
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NbN HEB mixers, anti-reflection coating |
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Parylene C was investigated as anti-reflection coating for silicon at terahertz frequencies. Measurements with a Fourier-transform spectrometer show that the transmittance of pure silicon can be improved by about 30% when applying a layer of Parylene C with a quarter wavelength optical thickness. The 10% bandwidth of this coating extends from 1.5 to 3 THz for a center frequency of 2.3–2.5 THz, where the transmittance is constant. Heterodyne measurements demonstrate that the noise temperature of a hot-electron-bolometric mixer can be reduced significantly by coating the silicon lens of the hybrid antenna with a quarter wavelength Parylene C layer. Compared to the same mixer with an uncoated lens the improvement is about 30% at a frequency of 2.5 THz. |
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1350-4495 |
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