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| Author | Słysz, W.; Wegrzecki, M.; Bar, J.; Grabiec, P.; Górska, M.; Zwiller, V.; Latta, C.; Böhi, P.; Pearlman, A.J.; Cross, A.S.; Pan, D.; Kitaygorsky, J.; Komissarov, I.; Verevkin, A.; Milostnaya, I.; Korneev, A.; Minayeva, O.; Chulkova, G.; Smirnov, K.; Voronov, B.; Gol’tsman, G.N.; Sobolewski, R. | ||||
| Title | Fibre-coupled, single photon detector based on NbN superconducting nanostructures for quantum communications | Type  |
Journal Article | ||
| Year | 2007 | Publication | J. Modern Opt. | Abbreviated Journal | J. Modern Opt. |
| Volume | 54 | Issue | 2-3 | Pages | 315-326 |
| Keywords | NbN SSPD, SNSPD | ||||
| Abstract | We present a novel, two-channel, single photon receiver based on two fibre-coupled, NbN, superconducting, single photon detectors (SSPDs). The SSPDs are nanostructured superconducting meanders and are known for ultrafast and efficient detection of visible-to-infrared photons. Coupling between the NbN detector and optical fibre was achieved using a micromechanical photoresist ring placed directly over the SSPD, holding the fibre in place. With this arrangement, we obtained coupling efficiencies up to ∼30%. Our experimental results showed that the best receiver had a near-infrared system quantum efficiency of 0.33% at 4.2 K. The quantum efficiency increased exponentially with the photon energy increase, reaching a few percent level for visible-light photons. The photoresponse pulses of our devices were limited by the meander high kinetic inductance and had the rise and fall times of approximately 250 ps and 5 ns, respectively. The receiver's timing jitter was in the 37 to 58 ps range, approximately 2 to 3 times larger than in our older free-space-coupled SSPDs. We stipulate that this timing jitter is in part due to optical fibre properties. Besides quantum communications, the two-detector arrangement should also find applications in quantum correlation experiments. | ||||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0950-0340 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1434 | |||
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| Author | Baselmans, J. J. A.; Baryshev, A.; Reker, S. F.; Hajenius, M.; Gao, J. R.; Klapwijk, T. M.; Voronov, B.; Gol’tsman, G. | ||||
| Title | Influence of the direct response on the heterodyne sensitivity of hot electron bolometer mixers | Type |
Journal Article | ||
| Year | 2006 | Publication | J. Appl. Phys. | Abbreviated Journal | J. Appl. Phys. |
| Volume | 100 | Issue | 8 | Pages | 084510 (1 to 7) |
| Keywords | NbN HEB mixers | ||||
| Abstract | We present a detailed experimental study of the direct detection effect in a small volume (0.15μm×1μm×3.5nm) quasioptical NbN phonon cooled hot electron bolometer mixer at 673GHz. We find that the small signal noise temperature, relevant for an astronomical observation, is 20% lower than the noise temperature obtained using 300 and 77K calibration loads. In a separate set of experiments we show that the direct detection effect is caused by a combination of bias current reduction when switching from the 77 to the 300K load in combination with the bias current dependence of the receiver gain. The bias current dependence of the receiver gain is shown to be mainly caused by the current dependence of the mixer gain. |
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| Language | Summary Language | Original Title | |||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0021-8979 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1442 | |||
| Permanent link to this record | |||||
| Author | Kooi, J. W.; Baselmans, J. J. A.; Baryshev, A.; Schieder, R.; Hajenius, M.; Gao, J.R.; Klapwijk, T. M.; Voronov, B.; Gol’tsman, G. | ||||
| Title | Stability of heterodyne terahertz receivers | Type |
Journal Article | ||
| Year | 2006 | Publication | J. Appl. Phys. | Abbreviated Journal | J. Appl. Phys. |
| Volume | 100 | Issue | 6 | Pages | 064904 (1 to 9) |
| Keywords | NbN HEB mixers | ||||
| Abstract | In this paper we discuss the stability of heterodyne terahertz receivers based on small volume NbN phonon cooled hot electron bolometers (HEBs). The stability of these receivers can be broken down in two parts: the intrinsic stability of the HEB mixer and the stability of the local oscillator (LO) signal injection scheme. Measurements show that the HEB mixer stability is limited by gain fluctuations with a 1∕f spectral distribution. In a 60MHz noise bandwidth this results in an Allan variance stability time of ∼0.3s. Measurement of the spectroscopic Allan variance between two intermediate frequency (IF) channels results in a much longer Allan variance stability time, i.e., 3s between a 2.5 and a 4.7GHz channel, and even longer for more closely spaced channels. This implies that the HEB mixer 1∕f noise is strongly correlated across the IF band and that the correlation gets stronger the closer the IF channels are spaced. In the second part of the paper we discuss atmospheric and mechanical system stability requirements on the LO-mixer cavity path length. We calculate the mixer output noise fluctuations as a result of small perturbations of the LO-mixer standing wave, and find very stringent mechanical and atmospheric tolerance requirements for receivers operating at terahertz frequencies. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Summary Language | Original Title | |||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0021-8979 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1444 | |||
| Permanent link to this record | |||||
| Author | Jiang, Ling; Miao, Wei; Zhang, Wen; Li, Ning; Lin, Zhen Hui; Yao, Qi Jun; Shi, Sheng-Cai; Svechnikov, S. I.; Vakhtomin, Y. B.; Antipov, S. V.; Voronov, B. M.; Kaurova, N. S.; Gol'tsman, G. N. | ||||
| Title | Characterization of a quasi-optical NbN superconducting HEB mixer | Type |
Journal Article | ||
| Year | 2006 | Publication | IEEE Trans. Microwave Theory Techn. | Abbreviated Journal | IEEE Trans. Microwave Theory Techn. |
| Volume | 54 | Issue | 7 | Pages | 2944-2948 |
| Keywords | NbN HEB mixers | ||||
| Abstract | In this paper, the performance of a quasi-optical NbN superconducting hot-electron bolometer (HEB) mixer, cryogenically cooled by a close-cycled 4-K refrigerator, is thoroughly investigated at 300, 500, and 850 GHz. The lowest receiver noise temperatures measured at the respective three frequencies are 1400, 900, and 1350 K, which can go down to 659, 413, and 529 K, respectively, after correcting the loss and associated noise contribution of the quasi-optical system before the measured superconducting HEB mixer. The stability of the quasi-optical superconducting HEB mixer is also investigated here. The Allan variance time measured with a local oscillator pumping at 500 GHz and an IF bandwidth of 110 MHz is 1.5 s at the dc-bias voltage exhibiting the lowest noise temperature and increases to 2.5 s at a dc bias twice that voltage. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0018-9480 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1448 | |||
| Permanent link to this record | |||||
| Author | Kerman, A. J.; Dauler, E. A.; Keicher, W. E.; Yang, J. K. W.; Berggren, K. K.; Gol’tsman, G.; Voronov, B. | ||||
| Title | Kinetic-inductance-limited reset time of superconducting nanowire photon counters | Type |
Journal Article | ||
| Year | 2006 | Publication | Appl. Phys. Lett. | Abbreviated Journal | Appl. Phys. Lett. |
| Volume | 88 | Issue | 11 | Pages | 111116 (1 to 3) |
| Keywords | NbN SSPD, SNSPD | ||||
| Abstract | We investigate the recovery of superconducting NbN-nanowire photon counters after detection of an optical pulse at a wavelength of 1550nm, and present a model that quantitatively accounts for our observations. The reset time is found to be limited by the large kinetic inductance of these nanowires, which forces a tradeoff between counting rate and either detection efficiency or active area. Devices of usable size and high detection efficiency are found to have reset times orders of magnitude longer than their intrinsic photoresponse time. The authors acknowledge D. Oates and W. Oliver (MIT Lincoln Laboratory), S.W. Nam, A. Miller, and R. Hadfield (NIST) and R. Sobolewski, A. Pearlman, and A. Verevkin (University of Rochester) for helpful discussions and technical assistance. This work made use of MIT’s shared scanning-electron-beam-lithography facility in the Research Laboratory of Electronics. This work is sponsored by the United States Air Force under Air Force Contract No. FA8721-05-C-0002. Opinions, interpretations, recommendations and conclusions are those of the authors and are not necessarily endorsed by the United States Government. |
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| Publisher | Place of Publication | Editor | |||
| 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 | 1453 | |||
| Permanent link to this record | |||||