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| Author | Verevkin, A. A.; Ptitsina, N. G.; Smirnov, K. V.; Goltsman, G. N.; Gershenson, E. M.; Yngvesson, K. S. | ||||
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Direct measurements of electron energy relaxation times at an AlGaAs/GaAs heterointerface in the optical phonon scattering range | Type | Conference Article | ||
| Year | 1997 | Publication | Proc. 4-th Int. Semicond. Device Research Symp. | Abbreviated Journal | Proc. 4-th Int. Semicond. Device Research Symp. |
| Volume | Issue | Pages | 55-58 | ||
| Keywords | 2DEG, AlGaAs/GaAs heterostructures | ||||
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| Notes | Approved | no | |||
| Call Number | Serial | 1602 | |||
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| Author | Baryshev, A.; Baselmans, J. J. A.; Reker, S. F.; Hajenius, M.; Gao, J. R.; Klapwijk, T. M.; Vachtomin, Yu.; Maslennikov, S.; Antipov, S.; Voronov, B.; Gol'tsman, G. | ||||
| Title |
Direct detection effect in hot electron bolometer mixers | Type | Abstract | ||
| Year | 2005 | Publication | Proc. 16th Int. Symp. Space Terahertz Technol. | Abbreviated Journal | Proc. 16th Int. Symp. Space Terahertz Technol. |
| Volume | Issue | Pages | 463-464 | ||
| Keywords | NbN HEB mixers, effect of direct detection, direct detection effect | ||||
| Abstract | NbN phonon cooled hot electron bolometer (HEB) mixers are currently the most sensitive heterodyne detectors at frequencies above 1.2 THz. They combine a good sensitivity (8-15 times the quantum limit), an IF bandwidth of the order of 4-6 GHz and a wide RF bandwidth from 0.7-5.2 THz. However, for use in a space based observatory, such as Herschel, it is of vital importance that the Local Oscillator (LO) power requirement of the mixer is compatible with the low output power of present day THz LO sources. This can be achieved by reducing the mixer volume and critical current. However, the large RF bandwidth and low LO power requirement of such a mixer result in a direct detection effect, characterized by a change in the bias current of the HEB when changing the RF signal from a black body load at 300 K to one at 77 K. As a result the measured sensitivity using a 300 K and 77 K calibration load differs significantly from the small signal sensitivity relevant for astronomical observations. In this article we describe a set of dedicated experiments to characterize the direct detection effect for a small volume quasi-optical NbN phonon cooled HEB mixer. We measure the direct detection effect in a small volume (0.15 μm · 1 μm · 3.5 nm) quasi- optical NbN phonon cooled HEB mixer at 1.6 THz. We found that the small signal sensitivity of the receiver is underestimated by approximately 35% due to the direct detection effect and that the optimal operating point is shifted to higher bias voltages when using calibration loads of 300 K and 77 K. Using a 200 GHz wide band-pass filter at the 4.2 K the direct detection effect virtually disappears. Heterodyne response measurements using water vapor absorption line in a gas cell confirms the existence and a magnitude of a direct detection effect. We also propose a theoretical explanation using uniform electron heating model. This direct detection effect has important implications for the calibration procedure of these receivers in real telescope systems. We are developing Nb HEBs for a large-format, diffusion-cooled hot electron bolometer (HEB) array submillimeter camera. The goal is to produce a 64 pixel array together with the University of Arizona to be used on the HHT on Mt Graham. It is designed to detect in the 850 GHz atmospheric window. We have fabricated Nb HEBs using a new angle- deposition process, which had previously produced high quality Nb-Au bilayer HEB devices at Yale. [1] We have characterized these devices using heterodyne mixing at ~30 GHz to compare to 345 GHz tests at the University of Arizona. We can also directly compare our Nb HEB mixers to SIS mixers in this same 345 GHz system. This allows us to rigorously calibrate the system’s losses and extract the mixer noise temperature in a well characterized mixer block, before undertaking the 850 GHz system. Here we give a report on the initial devices we have fabricated and characterized. * Department of Applied Physics, Yale University ** Department of Astronomy, University of Arizona [1] Applied Physics Letters 84, Number 8; p.1404-7, Feb 23 (2004) | ||||
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| Notes | Approved | no | |||
| Call Number | Serial | 1475 | |||
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| Author | 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 | Issue | 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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| Notes | Approved | no | |||
| Call Number | Serial | 1436 | |||
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| Author | Elezov, M. S.; Ozhegov, R. V.; Goltsman, G. N.; Makarov, V.; Vinogradov, E. A.; Naumov, A. V.; Gladush, M. G.; Karimullin, K. R. | ||||
| Title |
Development of the experimental setup for investigation of latching of superconducting single-photon detector caused by blinding attack on the quantum key distribution system | Type | Conference Article | ||
| Year | 2017 | Publication | EPJ Web Conf. | Abbreviated Journal | EPJ Web Conf. |
| Volume | 132 | Issue | Pages | 01004 (1 to 2) | |
| Keywords | QKD, SSPD, SNSPD | ||||
| Abstract | Recently bright-light control of the SSPD has been demonstrated. This attack employed a “backdoor” in the detector biasing scheme. Under bright-light illumination, SSPD becomes resistive and remains “latched” in the resistive state even when the light is switched off. While the SSPD is latched, Eve can simulate SSPD single-photon response by sending strong light pulses, thus deceiving Bob. We developed the experimental setup for investigation of a dependence on latching threshold of SSPD on optical pulse length and peak power. By knowing latching threshold it is possible to understand essential requirements for development countermeasures against blinding attack on quantum key distribution system with SSPDs. | ||||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 2100-014X | ISBN | Medium | ||
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| Notes | Approved | no | |||
| Call Number | Serial | 1327 | |||
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| Author | Elezov, M. S.; Ozhegov, R. V.; Goltsman, G. N.; Makarov, V. | ||||
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Development of the experimental setup for investigation of latching of superconducting single-photon detector caused by blinding attack on the quantum key distribution system | Type | Conference Article | ||
| Year | 2017 | Publication | EPJ Web of Conferences | Abbreviated Journal | EPJ Web of Conferences |
| Volume | 132 | Issue | 2 | Pages | 2 |
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| Abstract | Recently bright-light control of the SSPD has been demonstrated. This attack employed a “backdoor†in the detector biasing scheme. Under bright-light illumination, SSPD becomes resistive and remains “latched†in the resistive state even when the light is switched off. While the SSPD is latched, Eve can simulate SSPD single-photon response by sending strong light pulses, thus deceiving Bob. We developed the experimental setup for investigation of a dependence on latching threshold of SSPD on optical pulse length and peak power. By knowing latching threshold it is possible to understand essential requirements for development countermeasures against blinding attack on quantum key distribution system with SSPDs. |
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| Notes | Approved | no | |||
| Call Number | RPLAB @ kovalyuk @ | Serial | 1116 | ||
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| Author | Semenov, A.; Richter, H.; Hübers, H.-W.; Smirnov, K.; Voronov, B.; Gol'tsman, G. | ||||
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Development of terahertz superconducting hot-electron bolometer mixers | Type | Conference Article | ||
| Year | 2003 | Publication | Proc. 6th European Conf. Appl. Supercond. | Abbreviated Journal | Proc. 6th European Conf. Appl. Supercond. |
| Volume | 181 | Issue | Pages | 2960-2965 | |
| Keywords | NbN HEB mixers | ||||
| Abstract | We present recent results of the development of phonon cooled hot-electron bolometric (HEB) mixers for airborne and balloon borne terahertz heterodyne receivers. Three iomportant issues have been addresses: the quality of NbN films the HEB mixers were made from, the spectral properties of the HEB mixers and the local oscillator power required for optical operation. Studies with an atomic force microscope indicate, that the performance of the HEB mixer might have been effected by the microstructure of the NbN film. Antenna gain and noise temperature were investigated at terahertz frequencies for a HEB embedded in either log-spiral or twin-slot feed antenna. Comparison suggests that at frequencies above 3 THz the spiral feed provides better overall performance. At 1.6 THz, a power of 2.5 µW was required from the local oscillator for optimal operation of the HEB mixer. | ||||
| Address | Sorrento, Italy | ||||
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| ISSN | ISBN | 0750309814, 978-0750309813 | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1505 | |||
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| Author | Zolotov, P. I.; Divochiy, A. V.; Vakhtomin, Y. B.; Morozov, P. V.; Seleznev, V. A.; Smirnov, K. V. | ||||
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Development of high-effective superconducting single-photon detectors aimed for mid-IR spectrum range | Type | Conference Article | ||
| Year | 2017 | Publication | J. Phys.: Conf. Ser. | Abbreviated Journal | J. Phys.: Conf. Ser. |
| Volume | 917 | Issue | Pages | 062037 | |
| Keywords | NbN SSPD, SNSPD | ||||
| Abstract | We report on development of superconducting single-photon detectors (SSPD) with high intrinsic quantum efficiency in the wavelength range 1.31 – 3.3 μm. By optimization of the NbN film thickness and its compound, we managed to improve detection efficiency of the detectors in the range up to 3.3 μm. Optimized devices showed intrinsic quantum efficiencies as high as 10% at mid-IR range. | ||||
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| ISSN | 1742-6588 | ISBN | Medium | ||
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| Notes | Approved | no | |||
| Call Number | Serial | 1233 | |||
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| Author | Semenov, A.; Richter, H.; Smirnov, A.; Günther, B.; Hübers, H.-W.; Il’in, K.; Siegel, M.; Gol’tsman, G.; Drakinskiy, V.; Merkel, H.; Karamarkovic, J. | ||||
| Title |
Development of HEB mixers for GREAT and for security screening | Type | Abstract | ||
| Year | 2007 | Publication | Proc. 18th Int. Symp. Space Terahertz Technol. | Abbreviated Journal | Proc. 18th Int. Symp. Space Terahertz Technol. |
| Volume | Issue | Pages | 184 | ||
| Keywords | NbN HEB mixers, GREAT | ||||
| Abstract | We report the study on the quasioptical coupling efficiency and the gain bandwidth of NbN hot-electron bolometer mixers developed for the 4.7 THz channel of the German receiver for Astronomy at THz-frequencies (GREAT) and for security screening at subterahertz frequencies. Radiation coupling efficiency and directive properties of integrated lens antennas with log-spiral, log-periodic and double-slot planar feeds coupled to a hot-electron bolometer were experimentally studied at frequencies from 1 THz to 6 THz and compared with simulations based on the method of moments and the physical-optics ray tracing. For all studied antennas the modeled spectral dependence of the coupling efficiency fits to the experimental data obtained with both Fourier transform spectroscopy and noise temperature measurements only if the complex impedance of the bolometer is explicitly taken into account. Our experimental data did not indicate any noticeable contribution of the quantum noise to the system noise temperature. The experimentally observed deviation of the beam pattern from the model prediction increases with frequency and is most likely due to a non- ideality of the presently used lenses. Study of the intermediate frequency mixer gain at local oscillator (LO) frequencies between 2.5 THz and 0.3 THz showed an increase of the gain bandwidth at low LO frequencies that was understood as the contribution of the direct interaction of magnetic vortices with the radiation field. We have found that the non- homogeneous hot-spot model more adequately describes variation of the intermediate frequency bandwidth with the applied local oscillator power than any of uniform mixer models. The state-of-the-day performance of the GREAT 4.7-THz channel and the 0.8-THz security scanner will be presented. | ||||
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| Notes | Approved | no | |||
| Call Number | Serial | 1420 | |||
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| Author | Elmanov, I.; Sardi, F.; Xia, K.; Kornher, T.; Kovalyuk, V.; Prokhodtsov, A.; An, P.; Kuzin, A.; Elmanova, A.; Goltsman, G.; Kolesov, R. | ||||
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Development of focusing grating couplers for lithium niobate on insulator platform | Type | Conference Article | ||
| Year | 2020 | Publication | J. Phys.: Conf. Ser. | Abbreviated Journal | J. Phys.: Conf. Ser. |
| Volume | 1695 | Issue | Pages | 012127 | |
| Keywords | grating couplers, lithium niobat | ||||
| Abstract | In this paper, we fabricate and experimentally study focusing grating couplers for lithium niobate on an insulator photonic platform. The transmittance of a waveguide equipped with in- and out-couplers with respect to the grating period is measured with and without silicon dioxide cladding applied. Our results show the influence of silicon dioxide cladding on the efficiency and the central wavelength of grating couplers and can be used to improve grating coupling efficiency. Our study is supported by numerical simulations. | ||||
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| ISSN | 1742-6588 | ISBN | Medium | ||
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| Notes | Approved | no | |||
| Call Number | Serial | 1180 | |||
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| Author | Zolotov, P.; Vakhtomin, Yu.; Divochiy, A.; Morozov, P.; Seleznev, V.; Smirnov, K | ||||
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Development of fast and high-effective single-photon detector for spectrum range up to 2.3 μm | Type | Conference Article | ||
| Year | 2017 | Publication | Proc. SPBOPEN | Abbreviated Journal | Proc. SPBOPEN |
| Volume | Issue | Pages | 439-440 | ||
| Keywords | SSPD, SNSPD | ||||
| Abstract | We present the results of development and testing of the single-photon-counting system operating in the wide spectrum rane up to 2.3 mcm. We managed to increase system detection efficiency up to 60% in the range of 1.7-2.3 mcm optimisation of the fabrication methods of superconducting single-photon detectors and application of the single-mode fiber with enlarged core diameter. | ||||
| Address | St. Petersburg, Russia | ||||
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| Notes | Approved | no | |||
| Call Number | Serial | 1255 | |||
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