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| Author | Gol'tsman, G. N.; Loudkov, D. N. | ||||
| Title | Terahertz superconducting hot-electron bolometer mixers and their application in radio astronomy | Type | Journal Article | ||
Year  |
2003 | Publication | Radiophys. Quant. Electron. | Abbreviated Journal | |
| Volume | 46 | Issue | 8/9 | Pages | 604-617 |
| Keywords | NbN HEB mixers | ||||
| Abstract | We review the latest developments, research, and radioastronomy applications of hot-electron bolometer (HEB) mixers operated in the terahertz waveband. The physical principles of operation of terahertz HEB mixers are presented, their manufacturing from ultrathin NbN films, the main HEB-mixer parameters and their measurement techniques are discussed, and practical terahertz radioastronomy projects based on heterodyne receivers with HEB mixers are considered. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0033-8443 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | UDC 537.312.62 | Approved | no | ||
| Call Number | Serial | 472 | |||
| Permanent link to this record | |||||
| Author | Semenov, A.; Engel, A.; Il'in, K.; Gol'tsman, G.; Siegel, M.; Hübers, H.-W. | ||||
| Title | Ultimate performance of a superconducting quantum detector | Type | Journal Article | ||
| Year |
2003 | Publication | Eur. Phys. J. Appl. Phys. | Abbreviated Journal | Eur. Phys. J. Appl. Phys. |
| Volume | 21 | Issue | 3 | Pages | 171-178 |
| Keywords | NbN SSPD, SNSPD | ||||
| Abstract | We analyze the ultimate performance of a superconducting quantum detector in order to meet requirements for applications in near-infrared astronomy and X-ray spectroscopy. The detector exploits a combined detection mechanism, in which avalanche quasiparticle multiplication and the supercurrent jointly produce a voltage response to a single absorbed photon via successive formation of a photon-induced and a current-induced normal hotspot in a narrow superconducting strip. The response time of the detector should increase with the photon energy providing energy resolution. Depending on the superconducting material and operation conditions, the cut-off wavelength for the single-photon detection regime varies from infrared waves to visible light. We simulated the performance of the background-limited infrared direct detector and X-ray photon counter utilizing the above mechanism. Low dark count rate and intrinsic low-frequency cut-off allow for realizing a background limited noise equivalent power of 10−20 W Hz−1/2 for a far-infrared direct detector exposed to 4-K background radiation. At low temperatures, the intrinsic response time of the counter is rather determined by diffusion of nonequilibrium electrons than by the rate of energy transfer to phonons. Therefore, thermal fluctuations do not hamper energy resolution of the X-ray photon counter that should be better than 10−3 for 6-keV photons. Comparison of new data obtained with a Nb based detector and previously reported results on NbN quantum detectors support our estimates of ultimate detector performance. | ||||
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| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1286-0042 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 534 | |||
| Permanent link to this record | |||||
| Author | Verevkin, A.; Slysz, W.; Pearlman, A.; Zhang, J.; Sobolewski, R.; Okunev, O.; Korneev, A.; Kouminov, P.; Smirnov, K.; Chulkova, G.; Gol’tsman, G. N.; Currie, M. | ||||
| Title | Real-time GHz-rate counting of infrared photons using nanostructured NbN superconducting detectors | Type | Conference Article | ||
| Year |
2003 | Publication | CLEO/QELS | Abbreviated Journal | CLEO/QELS |
| Volume | Issue | Pages | CThM8 | ||
| Keywords | NbN SSPD; SNSPD; Infrared; Quantum detectors; Detectors; Photon counting; Quantum communications; Quantum cryptography; Single photon detectors; Superconductors | ||||
| Abstract | We demonstrate that our ultrathin, nanometer-width NbN superconducting single-photon detectors are capable of above 1-GHz-frequency, real-time counting of near-infrared photons. The measured system jitter of the detector is below 15 ps. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Optical Society of America | Place of Publication | Editor | ||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | ISBN | Medium | |||
| Area | Expedition | Conference | Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference | ||
| Notes | Approved | no | |||
| Call Number | Serial | 1517 | |||
| Permanent link to this record | |||||
| Author | Khosropanah, Pourya | ||||
| Title | NbN and NbTiN hot electron bolometer THz mixers | Type | Book Whole | ||
| Year |
2003 | Publication | Chalmers University of Technology | Abbreviated Journal | |
| Volume | Issue | Pages | |||
| Keywords | HEB mixer, hot electron bolometer mixer, NbN, NbTiN, superconducting detector, heterodyne receiver, THz mixer, submillimeter mixer, quasioptical receiver, double slot antenna, twin slot antenna, spiral antenna, receiver noise, FTS, Fourier Transform Spectrometer | ||||
| Abstract | The thesis reports the development of Hot Electron Bolometer (HEB) mixers for radio astronomy heterodyne receivers in THz frequency range. Part of this work is the fabrication of HEB devices, which are based on NbN or NbTiN superconducting thin films (â‰<a4>5 nm). They are integrated with wideband spiral or double-slot planar antennas. The mixer chips are incorporated into a quasi-optical receiver. The experimental part of this work focuses on the characterization of the receiver as a whole, and the HEB mixers as a part. Double side band receiver noise temperature and the IF bandwidth are reported for frequencies from 0.7 THz up to 2.6 THz. The spectrum of the direct response of HEB integrated with dierent antennas are measured using Fourier Transform Spectrometer (FTS). The effect of the bolometer size on total receiver performance and the LO power requirements is also discussed. A high-yield and reliable process for fabrication of NbN HEB mixers have been achieved. Over 100 devices with different bolometer geometry, film property and also different antennas have been fabricated and measured. The measured data enables us to discuss the impact of different parameters to the receiver overall performance. This work has provided NbN HEB mixers to the following receivers: TREND (Terahertz REceiver with NbN HEB Device) operating at 1.25-1.5 THz, installed in AST/RO Submillimeter Wave Telescope, Amundsen/Scott South Pole Station, in 2002-2003. Band 6-low (1.410-1.700 THz) and 6-high (1.700-1.920 THz) of the HIFI (Heterodyne Instrument for Far Infra-red) in the Herschel Space Observatory, due to launch in 2007 by ESA (European Space Agency). Besides, there has been continuous efforts to develop better models to explain the mixer performance more accurately. They are based on two temperature model for electrons and phonons and solving one-dimensional heat balance equations along the bolometer. The principles of these models are illustrated and the calculated results are compared with measured data. |
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| Address | |||||
| Corporate Author | Thesis | Ph.D. thesis | |||
| Publisher | Chalmers University of Technology | Place of Publication | Göteborg | Editor | |
| Language | Summary Language | Original Title | |||
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| Series Volume | Series Issue | Edition | |||
| ISSN | ISBN | Medium | |||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 910 | |||
| Permanent link to this record | |||||
| Author | Baselmans, J. J. A.; Hajenius, M.; Gao, J. R.; Klapwijk, T. M.; de Korte, P. A. J.; Voronov, B.; Gol'tsman, G. | ||||
| Title | Noise performance of NbN hot electron bolometer mixers at 2.5 THz and its dependence on the contact resistance | Type | Conference Article | ||
| Year |
2003 | Publication | Proc. 14th Int. Symp. Space Terahertz Technol. | Abbreviated Journal | Proc. 14th Int. Symp. Space Terahertz Technol. |
| Volume | Issue | Pages | 11-19 | ||
| Keywords | NbN HEB mixers | ||||
| Abstract | NbN hot electron bolometer mixers (HEBM) are at this moment the best heterodyne receivers for frequencies above 1 Thz. However, the fabrication procedure of these devices is such that the quality of the interface between the NbN superconducting film and the contact structure is not under good control. The result is a low transparency interface between the bolometer itself and the contact/antenna structure. In this paper we report a detailed experimental study on a novel idea to increase the transparency of this interface. This leads to a record sensitivity and more reproducible performance. We compare identical bolometers, coupled with a spiral antenna, with different NbN bolometer-contact pad interfaces. We find that cleaning the NbN interface alone results in an increase in the noise temperature. However, cleaning the NbN interface and adding a thin additional superconductor prior to the gold contact deposition improves the noise temperature of the HEBm with more than a factor of 2. A device with a contact pad on top of an in-situ cleaned NbN film consisting of 10 nm of NbTiN and 40 nm of gold has a DSB noise temperature of 1050 K at 2.5 THz. | ||||
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| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1497 | |||
| Permanent link to this record | |||||