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| Author | Meledin, Denis; Pavolotsky, Alexey; Desmaris, Vincent.; Lapkin, Igor; Risacher, Christophe; Perez, Victor; Henke, Douglas; Nystrom, Olle; Sundin, Erik; Dochev, Dimitar; Pantaleev, Miroslav; Fredrixon, Mathias; Strandberg, Magnus; Voronov, Boris; Goltsman, Gregory; Belitsky, Victor | ||||
| Title | A 1.3-THz balanced waveguide HEB mixer for the APEX telescope | Type | Journal Article | ||
| Year | 2009 | Publication | IEEE Trans. Microw. Theory Techn. | Abbreviated Journal | |
| Volume | 57 | Issue | 1 | Pages | 89-98 |
| Keywords | HEB, mixer, waveguide, balanced, NbN | ||||
| Abstract | In this paper, we report about the development, fabrication, and characterization of a balanced waveguide hot electron bolometer (HEB) receiver for the Atacama Pathfinder EXperiment telescope covering the frequency band of 1.25–1.39 THz. The receiver uses a quadrature balanced scheme and two HEB mixers, fabricated from 4- to 5-nm-thick NbN film deposited on crystalline quartz substrate with an MgO buffer layer in between. We employed a novel micromachining method to produce all-metal waveguide parts at submicrometer accuracy (the main-mode waveguide dimensions are 90×180 μm). We present details on the mixer design and measurement results, including receiver noise performance, stability and “first-light†at the telescope site. The receiver yields a double-sideband noise temperature averaged over the RF band below 1200 K, and outstanding stability with a spectroscopic Allan time more than 200 s. | ||||
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| ISSN | 0018-9480 | ISBN | Medium | ||
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Approved | no | |||
| Call Number | RPLAB @ lobanovyury @ | Serial | 554 | ||
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| Author | Kawamura, J.; Blundell, R.; Tong, C.-Y. E.; Papa, D. C.; Hunter, T. R.; Paine, S. N.; Patt, F.; Gol'tsman, G.; Cherednichenko, S.; Voronov, B.; Gershenzon, E. | ||||
| Title | Superconductive hot-electron-bolometer mixer receiver for 800-GHz operation | Type | Journal Article | ||
| Year | 2000 | Publication | IEEE Trans. Microw. Theory Techn. | Abbreviated Journal | IEEE Trans. Microw. Theory Techn. |
| Volume | 48 | Issue | 4 | Pages | 683-689 |
| Keywords | NbN HEB mixers, LO power, local oscillator power, saturation, linearity, dynamic range | ||||
| Abstract | In this paper, we describe a superconductive hot-electron-bolometer mixer receiver designed to operate in the partially transmissive 350-μm atmospheric window. The receiver employs an NbN thin-film microbridge as the mixer element, in which the main cooling mechanism of the hot electrons is through electron-phonon interaction. At a local-oscillator frequency of 808 GHz, the measured double-sideband receiver noise temperature is TRX=970 K, across a 1-GHz intermediate-frequency bandwidth centered at 1.8 GHz. We have measured the linearity of the receiver and the amount of local-oscillator power incident on the mixer for optimal operation, which is PLO≈1 μW. This receiver was used in making observations as a facility instrument at the Heinrich Hertz Telescope, Mt. Graham, AZ, during the 1998-1999 winter observing season. | ||||
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| ISSN | 0018-9480 | ISBN | Medium | ||
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Approved | no | |||
| Call Number | RPLAB @ lobanovyury @ | Serial | 573 | ||
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| Author | Wei, Jian; Olaya, David; Karasik, Boris S.; Pereverzev, Sergey V.; Sergeev, Andrei V.; Gershenson, Michael E. | ||||
| Title | Ultrasensitive hot-electron nanobolometers for terahertz astrophysics | Type | Journal Article | ||
| Year | 2008 | Publication | Nature Nanotechnology | Abbreviated Journal | Nature Nanotech |
| Volume | 3 | Issue | 8 | Pages | 496-500 |
| Keywords | HEB, Ti/NbN, single terahertz photons, detection | ||||
| Abstract | The submillimetre or terahertz region of the electromagnetic spectrum contains approximately half of the total luminosity of the Universe and 98% of all the photons emitted since the Big Bang. This radiation is strongly absorbed in the Earth's atmosphere, so space-based terahertz telescopes are crucial for exploring the evolution of the Universe. Thermal emission from the primary mirrors in these telescopes can be reduced below the level of the cosmic background by active cooling, which expands the range of faint objects that can be observed. However, it will also be necessary to develop bolometers – devices for measuring the energy of electromagnetic radiation—with sensitivities that are at least two orders of magnitude better than the present state of the art. To achieve this sensitivity without sacrificing operating speed, two conditions are required. First, the bolometer should be exceptionally well thermally isolated from the environment; second, its heat capacity should be sufficiently small. Here we demonstrate that these goals can be achieved by building a superconducting hot-electron nanobolometer. Its design eliminates the energy exchange between hot electrons and the leads by blocking electron outdiffusion and photon emission. The thermal conductance between hot electrons and the thermal bath, controlled by electron–phonon interactions, becomes very small at low temperatures (10-16 WK-1 at 40 mK). These devices, with a heat capacity of 10-19 J K-1, are sufficiently sensitive to detect single terahertz photons in submillimetre astronomy and other applications based on quantum calorimetry and photon counting. |
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| ISSN | 1748-3387 | ISBN | Medium | ||
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Approved | no | |||
| Call Number | Serial | 576 | |||
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| Author | Korneeva, Y. P.; Manova, N. N.; Dryazgov, M. A.; Simonov, N. O.; Zolotov, P. I.; Korneev, A. A. | ||||
| Title | Influence of sheet resistance and strip width on the detection efficiency saturation in micron-wide superconducting strips and large-area meanders | Type | Journal Article | ||
| Year | 2021 | Publication | Supercond. Sci. Technol. | Abbreviated Journal | Supercond. Sci. Technol. |
| Volume | 34 | Issue | 8 | Pages | 084001 |
| Keywords | NbN SSPD, SMSPD | ||||
| Abstract | We report our study of detection efficiency (DE) saturation in wavelength range 400 – 1550 nm for the NbN Superconducting Microstrip Single-Photon Detectors (SMSPD) featuring the strip width up to 3 μm. We observe an expected decrease of the $DE$ saturation plateau with the increase of photon wavelength and decrease of film sheet resistance. At 1.7 K temperature DE saturation can be clearly observed at 1550 nm wavelength in strip with the width up to 2 μm when sheet resistance of the film is above 630Ω/sq. In such strips the length of the saturation plateau almost does not depend on the strip width. We used these films to make meander-shaped detectors with the light sensitive area from 20×20μm2 to a circle 50 μm in diameter. In the latter case, the detector with the strip width of 0.49 μm demonstrates saturation of DE up to 1064 nm wavelength. Although DE at 1310 and 1550 nm is not saturated, it is as high as 60%. The response time is limited by the kinetic inductance and equals to 20 ns(by 1/e decay), timing jitter is 44 ps. When coupled to multi-mode fibre large-area meanders demonstrate significantly higher dark count rate which we attribute to thermal background photons, thus advanced filtering technique would be required for practical applications. | ||||
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| ISSN | 0953-2048 | ISBN | Medium | ||
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Approved | no | |||
| Call Number | Serial | 1793 | |||
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| Author | 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 | Type | Journal Article | ||
| Year | 2011 | Publication | Appl. Phys. Lett. | Abbreviated Journal | Appl. Phys. Lett. |
| Volume | 98 | Issue | 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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Approved | no | |||
| Call Number | RPLAB @ gujma @ | Serial | 638 | ||
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| Author | Beck, M.; Klammer, M.; Lang, S.; Leiderer, P.; Kabanov, V. V.; Gol'tsman, G. N.; Demsar, J. | ||||
| Title | Energy-gap dynamics of superconducting NbN thin films studied by time-resolved terahertz spectroscopy | Type | Journal Article | ||
| Year | 2011 | Publication | Phys. Rev. Lett. | Abbreviated Journal | Phys. Rev. Lett. |
| Volume | 107 | Issue | 17 | Pages | 4 |
| Keywords | NbN thin film, energy gap dynamics | ||||
| Abstract | Using time-domain terahertz spectroscopy we performed direct studies of the photoinduced suppression and recovery of the superconducting gap in a conventional BCS superconductor 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 bare quasiparticle recombination rate, the Cooper pair-breaking rate and the electron-phonon coupling constant, λ=1.1±0.1, which is in excellent agreement with theoretical estimates. | ||||
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Approved | no | |||
| Call Number | RPLAB @ gujma @ | Serial | 641 | ||
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| Author | 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 | Type | 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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| Series Volume | Series Issue | Edition | |||
| ISSN | 1063-7850 | ISBN | Medium | ||
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Approved | no | |||
| Call Number | Serial | 1389 | |||
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| Author | Marsili, F.; Bitauld, D.; Fiore, A.; Gaggero, A.; Leoni, R.; Mattioli, F.; Divochiy, A.; Korneev, A.; Seleznev, V.; Kaurova, N.; Minaeva, O.; Goltsman, G. | ||||
| Title | Superconducting parallel nanowire detector with photon number resolving functionality | Type | Journal Article | ||
| Year | 2009 | Publication | J. Modern Opt. | Abbreviated Journal | J. Modern Opt. |
| Volume | 56 | Issue | 2-3 | Pages | 334-344 |
| Keywords | PNR; SSPD; SNSPD; thin superconducting films; photon number resolving detector; multiplication noise; telecom wavelength; NbN | ||||
| Abstract | We present a new photon number resolving detector (PNR), the Parallel Nanowire Detector (PND), which uses spatial multiplexing on a subwavelength scale to provide a single electrical output proportional to the photon number. The basic structure of the PND is the parallel connection of several NbN superconducting nanowires (100 nm-wide, few nm-thick), folded in a meander pattern. Electrical and optical equivalents of the device were developed in order to gain insight on its working principle. PNDs were fabricated on 3-4 nm thick NbN films grown on sapphire (substrate temperature TS=900C) or MgO (TS=400C) substrates by reactive magnetron sputtering in an Ar/N2 gas mixture. The device performance was characterized in terms of speed and sensitivity. The photoresponse shows a full width at half maximum (FWHM) as low as 660ps. PNDs showed counting performance at 80 MHz repetition rate. Building the histograms of the photoresponse peak, no multiplication noise buildup is observable and a one photon quantum efficiency can be estimated to be QE=3% (at 700 nm wavelength and 4.2 K temperature). The PND significantly outperforms existing PNR detectors in terms of simplicity, sensitivity, speed, and multiplication noise. | ||||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0950-0340 | ISBN | Medium | ||
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Approved | no | |||
| Call Number | RPLAB @ gujma @ | Serial | 701 | ||
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| Author | Tretyakov, Ivan; Ryabchun, Sergey; Finkel, Matvey; Maslennikov, Sergey; Maslennikova, Anna; Kaurova, Natalia; Lobastova, Anastasia; Voronov, Boris; Gol'tsman, Gregory | ||||
| Title | Ultrawide noise bandwidth of NbN hot-electron bolometer mixers with in situ gold contacts | Type | Journal Article | ||
| Year | 2011 | Publication | IEEE Trans. Appl. Supercond. | Abbreviated Journal | |
| 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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Approved | no | |||
| Call Number | RPLAB @ gujma @ | Serial | 716 | ||
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| Author | Lobanov, Y.; Tong, E.; Blundell, R.; Hedden, A.; Voronov, B.; Gol'tsman, G. | ||||
| Title | Large-signal frequency response of an HEB mixer: from 300 MHz to terahertz | Type | Journal Article | ||
| Year | 2011 | Publication | IEEE Trans. Appl. Supercond. | Abbreviated Journal | |
| Volume | 21 | Issue | 3 | Pages | 628-631 |
| Keywords | waveguide NbN HEB mixers | ||||
| Abstract | We present a study of the large signal frequency response of an HEB mixer over a wide frequency range. In our experiments, we have subjected the HEB mixer to incident electromagnetic radiation from 0.3 GHz to 1 THz. The mixer element is an NbN film deposited on crystalline quartz. The mixer chip is mounted in a waveguide cavity, coupled to free space with a diagonal horn. At microwave frequencies, electromagnetic radiation is applied through the coaxial bias port of the mixer block. At higher frequencies the input signal passes via the diagonal horn feed. At each frequency, the incident power is varied and a family of I-V curves is recorded. From the curves we identify 3 distinct regimes of operation of the mixer separated by the phonon relaxation frequency and the superconducting energy gap frequency observed at about 3 GHz and 660 GHz respectively. In this paper, we will present observed curves and discuss the results of our experiment. | ||||
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Approved | no | |||
| Call Number | RPLAB @ gujma @ | Serial | 719 | ||
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| Author | Lobanov, Y.V.; Tong, C.-Y.E.; Hedden, A.S.; Blundell, R.; Voronov, B.M.; Gol'tsman, G.N. | ||||
| Title | Direct measurement of the gain and noise bandwidths of HEB mixers | Type | Journal Article | ||
| Year | 2011 | Publication | IEEE Trans. Appl. Supercond. | Abbreviated Journal | IEEE Trans. Appl. Supercond. |
| Volume | 21 | Issue | 3 | Pages | 645-648 |
| Keywords | waveguide NbN HEB mixers | ||||
| Abstract | The intermediate frequency (IF) bandwidth of a hot electron bolometer (HEB) mixer is an important parameter of the mixer, in that it helps to determine its suitability for a given application. With the availability of wideband low noise amplifiers, it is simple to measure the performance of an HEB mixer over a wide range of IF at a fixed LO frequency using the standard Y-factor method. This in-situ method allows us to measure both the gain and noise bandwidths simultaneously. We have also measured mixer output impedance with a vector network analyser. Intrinsic time constant has been extracted from the impedance data and compared to the mixer's bandwidths determined from receiver Y-factor measurement. | ||||
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Approved | no | |||
| Call Number | RPLAB @ gujma @ | Serial | 720 | ||
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| Author | Kawakami, A; Saito, S.; Hyodo, M. | ||||
| Title | Fabrication of nano-antennas for superconducting Infrared detectors | Type | Journal Article | ||
| Year | 2011 | Publication | IEEE Trans. Appl. Supercond. | Abbreviated Journal | |
| Volume | 21 | Issue | 3 | Pages | 632-635 |
| Keywords | optical antennas, NbN/MgO/NbN/TiN/Al HEB, dipole antennas, IR, infrared | ||||
| Abstract | To improve the response performance of superconducting infrared detectors, we have developed a fabrication process for nano-antennas. A nano-antenna consists of a dipole antenna, and a superconducting thin film strip placed in the antenna's center. By measuring the transition temperature of the superconducting strips, we confirmed that their superconductivity maintained a good condition after the nano-antenna fabrication process. We also evaluated nano-antenna characteristics using Fourier transform infrared spectroscopy. The evaluated antenna length and width were respectively set at around 2400 nm and 400 nm, and the antennas were placed at intervals of several micrometers around the area of 1 mm2 . In an evaluation of spectral transmission characteristics, clear absorption caused by antenna effects was observed at around 1400 cm-1. High polarization dependencies were also observed. | ||||
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Approved | no | |||
| Call Number | Serial | 761 | |||
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| Author | Il'in, K. S.; Lindgren, M.; Currie, M. A.; Semenov, D.; Gol'tsman, G. N.; Sobolewski, Roman; Cherednichenko, S. I.; Gershenzon, E. M. | ||||
| Title | Picosecond hot-electron energy relaxation in NbN superconducting photodetectors | Type | Journal Article | ||
| Year | 2000 | Publication | Appl. Phys. Lett. | Abbreviated Journal | Appl. Phys. Lett. |
| Volume | 76 | Issue | 19 | Pages | 2752-2754 |
| Keywords | NbN HEB detectors, two-temperature model, IF bandwidth | ||||
| Abstract | We report time-resolved characterization of superconducting NbN hot-electron photodetectors using an electro-optic sampling method. Our samples were patterned into micron-size microbridges from 3.5-nm-thick NbN films deposited on sapphire substrates. The devices were illuminated with 100 fs optical pulses, and the photoresponse was measured in the ambient temperature range between 2.15 and 10.6 K (superconducting temperature transition TC). The experimental data agreed very well with the nonequilibrium hot-electron, two-temperature model. The quasiparticle thermalization time was ambient temperature independent and was measured to be 6.5 ps. The inelastic electron–phonon scattering time Ï„e–ph tended to decrease with the temperature increase, although its change remained within the experimental error, while the phonon escape time Ï„es decreased almost by a factor of two when the sample was put in direct contact with superfluid helium. Specifically, Ï„e–ph and Ï„es, fitted by the two-temperature model, were equal to 11.6 and 21 ps at 2.15 K, and 10(±2) and 38 ps at 10.5 K, respectively. The obtained value of Ï„e–ph shows that the maximum intermediate frequency bandwidth of NbN hot-electron phonon-cooled mixers operating at TC can reach 16(+4/–3) GHz if one eliminates the bolometric phonon-heating effect. | ||||
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| ISSN | 0003-6951 | ISBN | Medium | ||
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Approved | no | |||
| Call Number | Serial | 856 | |||
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| Author | Henrich, D.; Dorner,S.; Hofherr, M.; Il'in, K.; Semenov, A.; Heintze, E.; Scheffler, M.; Dressel, M.; Siegel, M. | ||||
| Title | Broadening of hot-spot response spectrum of superconducting NbN nanowire single-photon detector with reduced nitrogen content | Type | Journal Article | ||
| Year | 2012 | Publication | Abbreviated Journal | J. Appl. Phys. | |
| Volume | 112 | Issue | Pages | ||
| Keywords | SSPD, SNSPD, magnetron sputtering, spectrum, NbN film, nitrogen concentration | ||||
| Abstract | The spectral detection efficiency and the dark count rate of superconducting nanowire single-photon detectors (SNSPD) have been studied systematically on detectors made from thin NbN films with different chemical compositions. Reduction of the nitrogen content in the 4 nm thick NbN films results in a decrease of the dark count rates more than two orders of magnitude and in a red shift of the cut-off wavelength of the hot-spot SNSPD response. The observed phenomena are explained by an improvement of uniformity of NbN films that has been confirmed by a decrease of resistivity and an increase of the ratio of the measured critical current to the depairing current. The latter factor is considered as the most crucial for both the cut-off wavelength and the dark count rates of SNSPD. Based on our results we propose a set of criteria for material properties to optimize SNSPD in the infrared spectral region. VC 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4757625] |
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| Corporate Author | D. Henrich, S. Dorner, M. Hofherr, K. Il'in, A. Semenov, E. Heintze, M. Scheffler, M. Dressel, M. Siegel | Thesis | |||
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| Language | English | Summary Language | Original Title | Broadening of hot-spot response spectrum of superconducting NbN nanowire single-photon detector with reduced nitrogen content | |
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Approved | no | |||
| Call Number | RPLAB @ seleznev @ | Serial | 877 | ||
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| Author | Semenov, A. D.; Nebosis, R. S.; Gousev, Yu. P.; Heusinger, M. A.; Renk, K. F. | ||||
| Title | Analysis of the nonequilibrium photoresponse of superconducting films to pulsed radiation by use of a two-temperature model | Type | Journal Article | ||
| Year | 1995 | Publication | Phys. Rev. B | Abbreviated Journal | Phys. Rev. B |
| Volume | 52 | Issue | 1 | Pages | 581-590 |
| Keywords | HEB, NbN phonon scecific heat, Cp | ||||
| Abstract | Photoresponse of a superconducting film in the resistive state to pulsed radiation has been studied in the framework of a model assuming that two different effective temperatures can be assigned to the quasiparticle and phonon nonequilibrium distributions. The coupled electron-phonon-substrate system is described by a system of time-dependent energy-balance differential equations for effective temperatures. An analytical solution of the system is given and calculated voltage transients are compared with experimental photoresponse signals taking into account the radiation pulse shape and the time resolution of the readout electronics. It is supposed that a resistive state (vortices, fluxons, network of intergrain junctions, hot spots, phase slip centers) provides an ultrafast connection between electron temperature changes and changes of the film resistance and thus plays a minor role in the temporal evolution of the response. In accordance with experimental observations a two-component response was revealed from simulations. The slower component corresponds to a bolometric mechanism while the fast component is connected with the relaxation of the electron temperature. Calculated photoresponse transients are presented for different ratios of the electron and phonon specific heat, radiation pulse durations and fluences, and frequency band passes of registration electronics. From the amplitude of the bolometric component we determine the radiation energy absorbed in a film. This enables us to reveal an intrinsic electron-phonon scattering time even if it is much shorter than the time resolution of readout electronics. We analyze experimental voltage transients for NbN, YBa2Cu3O7, and TlBa2Ca2Cu3O9 superconducting films and find the electron-phonon interaction times at the transition temperatures of 17, 2.5, and 1.8 ps, respectively. The values are in reasonable agreement with data of other experiments. | ||||
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Approved | no | |||
| Call Number | Serial | 903 | |||
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