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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 | Issue | 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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Notes | Approved | no | |||
Call Number | Serial | 1366 | |||
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Author | Beck, Matthias; Leiderer, Paul; Kabanov, Viktor V.; Gol'tsman, Gregory; Helm, Manfred; Demsar, Jure | ||||
Title | Energy-gap dynamics of a superconductor NbN studied by time-resolved terahertz spectroscopy | Type | Abstract | ||
Year | 2012 | Publication | INIS | Abbreviated Journal | INIS |
Volume | 45 | Issue | 12 | Pages | 1-3 |
Keywords | NbN energy gap | ||||
Abstract | Using time-resolved terahertz (THz) spectroscopy we performed direct studies of the photoinduced suppression and recovery of the SC gap in a conventional SC NbN. Both processes are found to be strongly temperature and excitation density dependent. The analysis of the data with the established phenomenological Rothwarf-Taylor model enabled us to determine the important microscopic constants: the Cooper pair-breaking rate via phonon absorption and the bare quasiparticle recombination rate. From the latter we were able to extract the dimensionless electron-phonon coupling constant, λ=1.1±0.1, in excellent agreement with theoretical estimates. The technique also allowed us to determine the absorbed energy required to suppress SC, which in NbN equals the thermodynamic condensation energy (in cuprates the two differ by an order of magnitude). Finally, we present the first studies of dynamics following resonant excitation with intense narrow band THz pulses tuned to above and below the superconducting gap. These suggest an additional process, particularly pronounced near Tc, that could be attributed to amplification of SC via effective quasiparticle cooling. | ||||
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Notes | Approved | no | |||
Call Number | Serial | 1383 | |||
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Author | Pentin, I. V.; Smirnov, A. V.; Ryabchun, S. A.; Gol’tsman, G. N.; Vaks, V. L.; Pripolzin, S. I.; Paveliev, D. G. | ||||
Title | Heterodyne source of THz range based on semiconductor superlattice multiplier | Type | Conference Article | ||
Year | 2011 | Publication | IRMMW-THz | Abbreviated Journal | IRMMW-THz |
Volume | Issue | Pages | 1-2 | ||
Keywords | NbN HEB mixer, superlattice | ||||
Abstract | We present the results of our studies of the possibility of developing a heterodyne receiver incorporating a hot-electron bolometer mixer as the detector and a semiconductor superlattice multiplier driven by a reference synthesizer as the local oscillator. We observe that such a local oscillator offers enough power in the terahertz range to pump the HEB into the operating state. | ||||
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Notes | Approved | no | |||
Call Number | 6105209 | Serial | 1384 | ||
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Author | Ryabchun, S.; Smirnov, A.; Pentin, I.; Vakhtomin, Yu.; Smirnov, K.; Kaurova, N.; Voronov, B.; Goltsman, G. | ||||
Title | Superconducting single photon detector integrated with optical cavity | Type | Conference Article | ||
Year | 2011 | Publication | Proc. MLPLIT | Abbreviated Journal | Proc. MLPLIT |
Volume | Issue | Pages | 143-145 | ||
Keywords | NbN SSPD, cavity | ||||
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Address | Suzdal / Vladimir (Russia) | ||||
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Publisher | Modern laser physics and laser-information technologies for science and manufacture | Place of Publication | Editor | ||
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Area | Expedition | Conference | 1st international russian-chinese conference / youthschool-workshop | ||
Notes | September 23-28, 2011 | Approved | no | ||
Call Number | Serial | 1385 | |||
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Author | Maslennikova, A.; Larionov, P.; Ryabchun, S.; Smirnov, A.; Pentin, I.; Vakhtomin, Yu.; Smirnov, K.; Kaurova, N.; Voronov, B.; Goltsman, G. | ||||
Title | Noise equivalent power and dynamic range of NBN hot-electron bolometers | Type | Conference Article | ||
Year | 2011 | Publication | Proc. MLPLIT | Abbreviated Journal | Proc. MLPLIT |
Volume | Issue | Pages | 146-148 | ||
Keywords | NbN HEB | ||||
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Address | Suzdal / Vladimir (Russia) | ||||
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Publisher | Modern laser physics and laser-information technologies for science and manufacture | Place of Publication | Editor | ||
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Area | Expedition | Conference | 1st international russian-chinese conference / youthschool-workshop | ||
Notes | September 23-28, 2011 | Approved | no | ||
Call Number | Serial | 1386 | |||
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Author | Korneev, A.; Korneeva, Y.; Florya, I.; Voronov, B.; Goltsman, G. | ||||
Title | Spectral sensitivity of narrow strip NbN superconducting single-photon detector | Type | Conference Article | ||
Year | 2011 | Publication | Proc. SPIE | Abbreviated Journal | Proc. SPIE |
Volume | 8072 | Issue | Pages | 80720G (1 to 9) | |
Keywords | NbN SSPD, SNSPD | ||||
Abstract | Superconducting single-photon detector (SSPD) is patterned from 4-nm-thick NbN film deposited on sapphire substrate as a 100-nm-wide strip. Due to its high detection efficiency, low dark counts, and picosecond timing jitter SSPD has become a competitor to the InGaAs avalanche photodiodes at 1550 nm and longer wavelengths. Although the SSPD is operated at liquid helium temperature its efficient single-mode fibre coupling enabled its usage in many applications ranging from single-photon sources research to quantum cryptography. In our strive to increase the detection efficiency at 1550 nm and longer wavelengths we developed and fabricated SSPD with the strip almost twice narrower compared to the standard 100 nm. To increase the voltage response of the device we utilized cascade switching mechanism: we connected 50-nm-wide and 10-μm-long strips in parallel covering the area of 10 μmx10 μm. Absorption of a photon breaks the superconductivity in a strip leading to the bias current redistribution between other strips followed their cascade switching. As the total current of all the strips about is 1 mA by the order of magnitude the response voltage of such an SSPD is several times higher compared to the traditional meander-shaped SSPDs. In middle infrared (about 3 μm wavelength) these devices have the detection efficiency several times higher compared to the traditional SSPDs. | ||||
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Publisher | SPIE | Place of Publication | Editor | Fiurásek, J.; Prochazka, I. | |
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Area | Expedition | Conference | Photon Counting Applications, Quantum Optics, and Quantum Information Transfer and Processing III | ||
Notes | Approved | no | |||
Call Number | Serial | 1387 | |||
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Author | Lobanov, Yury V.; Tong, Cheuk-yu E.; Hedden, Abigail S.; Blundell, Raymond; Gol’tsman, Gregory N. | ||||
Title | Microwave-assisted measurement of the frequency response of terahertz HEB mixers with a Fourier transform spectrometer | Type | Conference Article | ||
Year | 2010 | Publication | Proc. 21th Int. Symp. Space Terahertz Technol. | Abbreviated Journal | Proc. 21th Int. Symp. Space Terahertz Technol. |
Volume | Issue | Pages | 420-423 | ||
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Abstract | We describe a novel method of operation of the HEB direct detector for use with a Fourier Transform Spectrometer. Instead of elevating the bath temperature, we have measured the RF response of waveguide HEB mixers by applying microwave radiation to select appropriate bias conditions. In our experiment, a microwave signal is injected into the HEB mixer via its IF port. By choosing an appropriate injection level, the device can be operated close to the desired operating point. Furthermore, we have shown that both thermal biasing and microwave injection can reproduce the same spectral response of the HEB mixer. However, with the use of microwave injection, there is no need to wait for the mixer to reach thermal equilibrium, so characterisation can be done in less time. Also, the liquid helium consumption for our wet cryostat is also reduced. We have demonstrated that the signal- to-noise ratio of the FTS measurements can be improved with microwave injection. | ||||
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Notes | Approved | no | |||
Call Number | Serial | 1394 | |||
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Author | Смирнов, Константин Владимирович | ||||
Title | Создание приборов на сверхпроводниковых счетчиках фотонов и методов диагностики КМОП микросхем, гетероструктур и лазеров на квантовых точках | Type | Report | ||
Year | 2009 | Publication | Abbreviated Journal | ||
Volume | Issue | Pages | |||
Keywords | NbN SSPD | ||||
Abstract | Этап №1 (дата окончания: 30.09.2009) Разработана методика изготовления сверхпроводниковых однофотонных детекторов (SSPD) с монокристаллической структурой пленки сверхмалой толщины. Изготовлены экспериментальные образцы сверхпроводниковых однофотонных детекторов (SSPD). Разработана методика пакетирования сверхпроводникового однофотонного детектора в оптический узел с одномодовым оптоволокном. Изготовлены экспериментальные образцы приемных модулей на основе однофотонных сверхпроводниковых детекторов из NbN-нанопленок. Этап №2 (дата окончания: 28.10.2009) Разработаны методы диагностики КМОП микросхем, гетероструктур и лазеров на квантовых точках и методика измерения мощности излучения полупроводниковых лазеров на квантовых точках с использованием сверхпроводниковых однофотонных детекторов (SSPD). Проведена технико-экономическая оценка рыночного потенциала полученных результатов. |
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Publisher | Министерство образования и науки РФ | Place of Publication | Editor | ||
Language | Russian | Summary Language | Original Title | ||
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Notes | Отчет о НИР/НИОКР; Министерство образования и науки РФ; Номер гранта (контракта): 02.513.11.3446; Дата гранта (контракта): 03.06.2009 | Approved | no | ||
Call Number | Serial | 1828 | |||
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Author | Goltsman, G. | ||||
Title | Superconducting NbN hot-electron bolometer mixer, direct detector and single-photon counter: from devices to systems | Type | Report | ||
Year | 2009 | Publication | 2-nd Int. Conf. EUROFLUX | Abbreviated Journal | 2-nd Int. Conf. EUROFLUX |
Volume | Issue | Pages | |||
Keywords | HEB, SSPD, SNSPD | ||||
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Address | Avignon, France | ||||
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Notes | Provided by the SAO/NASA Astrophysics Data System | Approved | no | ||
Call Number | Serial | 1398 | |||
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Author | Minaeva, O.; Divochiy, A.; Korneev, A.; Sergienko, A. V.; Goltsman, G. N. | ||||
Title | High speed infrared photon counting with photon number resolving superconducting single-photon detectors (SSPDs) | Type | Conference Article | ||
Year | 2009 | Publication | CLEO/Europe – EQEC | Abbreviated Journal | CLEO/Europe – EQEC |
Volume | Issue | Pages | |||
Keywords | SSPD, SNSPD | ||||
Abstract | A review of development and characterization of the nanostructures consisting of several meander sections, all connected in parallel was presented. Such geometry leads to a significant decrease of the kinetic inductance, without a decrease of the SSPD active area. A new type of SSPDs possess the QE of large-active- area devices, but, simultaneously, allows achieving short response times and the GHz-counting rate. This new generation of superconducting detectors has another significant advantage for quantum key distribution, they have a photon number resolving capability and can distinguish more photons. | ||||
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Notes | Approved | no | |||
Call Number | Serial | 1399 | |||
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