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Author | Korneev, A.; Kouminov, P.; Matvienko, V.; Chulkova, G.; Smirnov, K.; Voronov, B.; Gol'tsman, G. N.; Currie, M.; Lo, W.; Wilsher, K.; Zhang, J.; Słysz, W.; Pearlman, A.; Verevkin, A.; Sobolewski, Roman | ||||
Title | Sensitivity and gigahertz counting performance of NbN superconducting single-photon detectors | Type | Journal Article | ||
Year | 2004 | Publication | Appl. Phys. Lett. | Abbreviated Journal | Appl. Phys. Lett. |
Volume | 84 | Issue | 26 | Pages | 5338-5340 |
Keywords | SSPD, NEP, QE | ||||
Abstract | We have measured the quantum efficiencysQEd, GHz counting rate, jitter, and noise-equivalentpowersNEPdof nanostructured NbN superconducting single-photon detectorssSSPDsdin thevisible to infrared radiation range. Our 3.5-nm-thick and 100- to 200-nm-wide meander-typedevices(total area 10310mm2), operating at 4.2 K, exhibit an experimental QE of up to 20% inthe visible range and,10% at 1.3 to 1.55mm wavelength and are potentially sensitive up tomidinfrareds,10mmdradiation. The SSPD counting rate was measured to be above 2 GHz withjitter,18 ps, independent of the wavelength. The devices’ NEP varies from,10−17W/Hz1/2for1.55mm photons to,10−20W/Hz1/2for visible radiation. Lowering the SSPD operatingtemperature to 2.3 K significantly enhanced its performance, by increasing the QE to,20% andlowering the NEP level to,3310−22W/Hz1/2, both measured at 1.26mm wavelength. | ||||
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ISSN | 0003-6951 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | Serial | 532 | |||
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Author | Baselmans, J. J. A.; Hajenius, M.; Gao, J. R.; Klapwijk, T. M.; de Korte, P. A. J.; Voronov, B.; Gol'tsman, G. | ||||
Title | Doubling of sensitivity and bandwidth in phonon cooled hot electron bolometer mixers | Type | Journal Article | ||
Year | 2004 | Publication | Appl. Phys. Lett. | Abbreviated Journal | Appl. Phys. Lett. |
Volume | 84 | Issue | 11 | Pages | 1958-1960 |
Keywords | NbN HEB mixers | ||||
Abstract | We demonstrate that the performance of NbN lattice cooled hot electron bolometer mixers depends strongly on the interface quality between the bolometer and the contact structure. We show experimentally that both the receiver noise temperature and the gain bandwidth can be improved by more than a factor of 2 by cleaning the interface and adding an additional superconducting interlayer to the contact pad. Using this we obtain a double sideband receiver noise temperature TN,DSB=950 K at 2.5 THz and 4.3 K, uncorrected for losses in the optics. At the same bias point, we obtain an IF gain bandwidth of 6 GHz. |
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Notes | Approved | no | |||
Call Number | Serial | 352 | |||
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Author | Verevkin, A.; Zhang, J.; Sobolewski, Roman; Lipatov, A.; Okunev, O.; Chulkova, G.; Korneev, A.; Smirnov, K.; Gol'tsman, G. N.; Semenov, A. | ||||
Title | Detection efficiency of large-active-area NbN single-photon superconducting detectors in the ultraviolet to near-infrared range | Type | Journal Article | ||
Year | 2002 | Publication | Appl. Phys. Lett. | Abbreviated Journal | |
Volume | 80 | Issue | 25 | Pages | 4687-4689 |
Keywords | NbN SSPD, SNSPD, QE | ||||
Abstract | We report our studies on spectral sensitivity of meander-type, superconducting NbN thin-film single-photon detectors (SPDs), characterized by GHz counting rates of visible and near-infrared photons and negligible dark counts. Our SPDs exhibit experimentally determined quantum efficiencies ranging from ∼0.2% at the 1.55 μm wavelength to ∼70% at 0.4 μm. Spectral dependences of the detection efficiency (DE) at the 0.4 to 3.0-μm-wavelength range are presented. The exponential character of the DE dependence on wavelength, as well as its dependence versus bias current, is qualitatively explained in terms of superconducting fluctuations in our ultrathin, submicron-width superconducting stripes. The DE values of large-active-area NbN SPDs in the visible range are high enough for modern quantum communications. | ||||
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Notes | Approved | no | |||
Call Number | Serial | 331 | |||
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Author | Gol’tsman, G. N.; Okunev, O.; Chulkova, G.; Lipatov, A.; Semenov, A.; Smirnov, K.; Voronov, B.; Dzardanov, A.; Williams, C.; Sobolewski, R. | ||||
Title | Picosecond superconducting single-photon optical detector | Type | Journal Article | ||
Year | 2001 | Publication | Appl. Phys. Lett. | Abbreviated Journal | Appl. Phys. Lett. |
Volume | 79 | Issue | 6 | Pages | 705-707 |
Keywords | NbN SSPD, SNSPD | ||||
Abstract | We experimentally demonstrate a supercurrent-assisted, hotspot-formation mechanism for ultrafast detection and counting of visible and infrared photons. A photon-induced hotspot leads to a temporary formation of a resistive barrier across the superconducting sensor strip and results in an easily measurable voltage pulse. Subsequent hotspot healing in ∼30 ps time frame, restores the superconductivity (zero-voltage state), and the detector is ready to register another photon. Our device consists of an ultrathin, very narrow NbN strip, maintained at 4.2 K and current-biased close to the critical current. It exhibits an experimentally measured quantum efficiency of ∼20% for 0.81 μm wavelength photons and negligible dark counts. | ||||
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ISSN | 0003-6951 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | Serial | 1543 | |||
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Author | Semenov, A. D.; Hübers, H.-W.; Schubert, J.; Gol'tsman, G. N.; Elantiev, A. I.; Voronov, B. M.; Gershenzon, E. M. | ||||
Title | Design and performance of the lattice-cooled hot-electron terahertz mixer | Type | Journal Article | ||
Year | 2000 | Publication | J. Appl. Phys. | Abbreviated Journal | J. Appl. Phys. |
Volume | 88 | Issue | 11 | Pages | 6758-6767 |
Keywords | HEB mixer, charge imbalance, HF current distribution | ||||
Abstract | We present the measurements and the theoreticalmodel of the frequency-dependent noise temperature of a superconductor lattice-cooled hot-electron bolometer mixer in the terahertz frequency range. The increase of the noise temperature with frequency is a cumulative effect of the nonuniform distribution of the high-frequency current in the bolometer and the charge imbalance, which occurs at the edges of the normal domain and at the contacts with normal metal. We show that under optimal operation the fluctuation sensitivity of the mixer is determined by thermodynamic fluctuations of the noise power, whereas at small biases there appears additional noise, which is probably due to the flux flow. We propose the prescription of how to minimize the influence of the current distribution on the mixer performance. | ||||
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Series Volume | Series Issue | Edition | |||
ISSN | 0021-8979 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | Serial | 306 | |||
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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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Language | Summary Language | Original Title | |||
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Series Volume | Series Issue | Edition | |||
ISSN | 0003-6951 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | Serial | 856 | |||
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Author | Il’in, K. S.; Milostnaya, I. I.; Verevkin, A. A.; Gol’tsman, G. N.; Gershenzon, E. M.; Sobolewski, R. | ||||
Title | Ultimate quantum efficiency of a superconducting hot-electron photodetector | Type | Journal Article | ||
Year | 1998 | Publication | Appl. Phys. Lett. | Abbreviated Journal | Appl. Phys. Lett. |
Volume | 73 | Issue | 26 | Pages | 3938-3940 |
Keywords | NbN SSPD, SNSPD | ||||
Abstract | The quantum efficiency and current and voltage responsivities of fast hot-electron photodetectors, fabricated from superconducting NbN thin films and biased in the resistive state, have been shown to reach values of 340, 220 A/W, and 4×104 V/W, respectively, for infrared radiation with a wavelength of 0.79 μm. The characteristics of the photodetectors are presented within the general model, based on relaxation processes in the nonequilibrium electron heating of a superconducting thin film. The observed, very high efficiency and sensitivity of the superconductor absorbing the photon are explained by the high multiplication rate of quasiparticles during the avalanche breaking of Cooper pairs. |
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Series Volume | Series Issue | Edition | |||
ISSN | 0003-6951 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | Serial | 1579 | |||
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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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Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | Serial | 911 | |||
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Author | Ekstörm, H.; Kollberg, E.; Yagoubov, P.; Gol'tsman, G.; Gershenzon, E.; Yngvesson, S. | ||||
Title | Gain and noise bandwidth of NbN hot-electron bolometric mixers | Type | Journal Article | ||
Year | 1997 | Publication | Appl. Phys. Lett. | Abbreviated Journal | Appl. Phys. Lett. |
Volume | 70 | Issue | 24 | Pages | 3296-3298 |
Keywords | NbN HEB mixers, conversion loss, conversion gain, U-factor technique | ||||
Abstract | We have measured the noise performance and gain bandwidth of 35 Å thin NbN hot-electron mixers integrated with spiral antennas on silicon substrate lenses at 620 GHz. The best double-sideband receiver noise temperature is less than 1300 K with a 3 dB bandwidth of ≈5 GHz. The gain bandwidth is 3.2 GHz. The mixer output noise dominated by thermal fluctuations is 50 K, and the intrinsic conversion gain is about −12 dB. Without mismatch losses and excluding the loss from the beamsplitter, we expect to achieve a receiver noise temperature of less than 700 K. | ||||
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Notes | Approved | no | |||
Call Number | Serial | 279 | |||
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Author | Kawamura, J.; Blundell, R.; Tong, C.-yu E.; Gol’tsman, G.; Gershenzon, E.; Voronov, B.; Cherednichenko, S. | ||||
Title | Low noise NbN lattice-cooled superconducting hot-electron bolometric mixers at submillimeter wavelengths | Type | Journal Article | ||
Year | 1997 | Publication | Appl. Phys. Lett. | Abbreviated Journal | Appl. Phys. Lett. |
Volume | 70 | Issue | 12 | Pages | 1619-1621 |
Keywords | NbN HEB mixers | ||||
Abstract | Lattice-cooled superconducting hot-electron bolometric mixers are used in a submillimeter-wave waveguide heterodyne receiver. The mixer elements are niobium nitride film with 3.5 nm thickness and ∼10 μm2 area. The local oscillator power for optimal performance is estimated to be 0.5 μW, and the instantaneous bandwidth is 2.2 GHz. At an intermediate frequency centered at 1.4 GHz with 200 MHz bandwidth, the double sideband receiver noise temperature is 410 K at 430 GHz. The receiver has been used to detect molecular line emission in a laboratory gas cell. | ||||
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Language | Summary Language | Original Title | |||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-6951 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | Serial | 1599 | |||
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