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| Author | Lobanov, Y. V.; Tong, Cheuk-Yu E.; Hedden, A. S.; Blundell, R.; Gol'tsman, G. N. | ||||
| Title | Microwave-assisted슠measurement슠of the슠frequency슠response슠of슠terahertz슠HEB슠mixers슠with a슠fourier슠transform슠spectrometer | Type | Conference Article | ||
| Year | 2010 | Publication | 21st International Symposium on Space Terahertz Technology | Abbreviated Journal | 21st ISSTT |
| Volume | Issue  |
Pages | 420-423 | ||
| Keywords | HEB mixer | ||||
| 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 signalto-noise ratio of the FTS measurements can be improved with microwave injection. | ||||
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| Notes | Approved | no | |||
| Call Number | RPLAB @ gujma @ | Serial | 725 | ||
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| Author | Kramer, B.; Chen, C-C.; Volakis, J.D. | ||||
| Title | The development of a mini-UWB antenna | Type | Journal Article | ||
| Year | 2004 | Publication | Measurement and Techniques Association Symposium | Abbreviated Journal | AMTA |
| Volume | Issue |
Pages | 6 | ||
| Keywords | optical antennas; Ultra Wide Band; Spiral Antenna, Dielectric Loading | ||||
| Abstract | There is a great interest in the automotive and military sectors for small and broadband antennas that meet modern communication needs. These needs require ultra-wide bandwidth (>10:1) UWB antennas, such as the spiral antenna. However, the physical size at the low-frequency end typically becomes too large for practical applications. To reduce the size of the antenna, miniaturization techniques must be employed such as the use of high-contrast dielectric materials. Size reduction using high-contrast materials has been demonstrated for narrowband antennas, such as patch antennas, but not for broadband antennas to our knowledge. Therefore, the concept of miniaturizing a broadband spiral antenna using dielectric materials will be investigated experimentally and numerically.Issues that arise from dielectric loading such as impedance reduction will also be addressed. It will be shown using the results from these studies that there are practical limitations to the amount of miniaturization which can be achieved. | ||||
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| Notes | Approved | no | |||
| Call Number | RPLAB @ gujma @ | Serial | 751 | ||
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| Author | Tang, Liang; Kocabas, Sukru Ekin; Latif, Salman; Okyay, Ali K.; Ly-Gagnon, Dany-Sebastien; Saraswat, Krishna C.; Miller, David A. B. | ||||
| Title | Nanometre-scale germanium photodetector enhanced by a near-infrared dipole antenna | Type | Journal Article | ||
| Year | 2008 | Publication | Nature Photonics | Abbreviated Journal | |
| Volume | 2 | Issue |
Pages | 226-229 | |
| Keywords | optical antennas | ||||
| Abstract | A critical challenge for the convergence of optics and electronics is that the micrometre scale of optics is significantly larger than the nanometre scale of modern electronic devices. In the conversion from photons to electrons by photodetectors, this size incompatibility often leads to substantial penalties in power dissipation, area, latency and noise. A photodetector can be made smaller by using a subwavelength active region; however, this can result in very low responsivity because of the diffraction limit of the light. Here we exploit the idea of a half-wave Hertz dipole antenna (length approx 380 nm) from radio waves, but at near-infrared wavelengths (length approx 1.3 microm), to concentrate radiation into a nanometre-scale germanium photodetector. This gives a polarization contrast of a factor of 20 in the resulting photocurrent in the subwavelength germanium element, which has an active volume of 0.00072 microm3, a size that is two orders of magnitude smaller than previously demonstrated detectors at such wavelengths. | ||||
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| Notes | Approved | no | |||
| Call Number | Serial | 858 | |||
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| Author | - | ||||
| Title | ГОСТ Р 15.011-96. Патентные исследования. Содержание и порядок проведения | Type | Book Whole | ||
| Year | 1996 | Publication | Abbreviated Journal | ||
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| Keywords | gost, patents, detproj | ||||
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| Notes | Approved | no | |||
| Call Number | Serial | 865 | |||
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| Author | Julia Toussaint, Roman Grüner, Marco Schubert, Torsten May, Hans-Georg Meyer, Benjamin Dietzek, Jürgen Popp, Matthias Hofherr, Matthias Arndt, Dagmar Henrich, Konstantin Il'in, and Michael Siegel | ||||
| Title | Superconducting single-photon counting system for optical experiments requiring time-resolution in the picosecond range | Type | Journal Article | ||
| Year | 2012 | Publication | Abbreviated Journal | AIP REVIEW OF SCIENTIFIC INSTRUMENTS | |
| Volume | 83 | Issue |
Pages | ||
| Keywords | SSPD, picosecond, time-resolution | ||||
| Abstract | We have developed a cryogenic measurement system for single-photon counting, which can be used in optical experiments requiring high time resolution in the picosecond range. The system utilizes niobium nitride superconducting nanowire single-photon detectors which are integrated in a timecorrelated single-photon counting (TCSPC) setup. In this work, we describe details of the mechanical design, the electrical setup, and the cryogenic optical components. The performance of the complete system in TCSPC mode is tentatively benchmarked using 140 fs long laser pulses at a repetition frequency of 75MHz. Due to the high temporal stability of these pulses, the measured time resolution of 35 ps (FWHM) is limited by the timing jitter of the measurement system. The result was crosschecked in a Coherent Anti-stokes Raman Scattering (CARS) setup, where scattered pulses from a β-barium borate crystal have been detected with the same time resolution. |
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| Notes | Approved | no | |||
| Call Number | RPLAB @ seleznev @ | Serial | 885 | ||
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