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Mel’nikov, A. P., Gurvich, Y. A., Shestakov, L. N., & Gershenzon, E. M. (2001). Magnetic field effects on the nonohmic impurity conduction of uncompensated crystalline silicon. Jetp Lett., 73(1), 44–47.
Abstract: The impurity conduction of a series of crystalline silicon samples with the concentration of major impurity N ≈ 3 × 1016 cm−3 and with a varied, but very small, compensation K was measured as a function of the electric field E in various magnetic fields H-σ(H, E). It was found that, at K < 10−3 and in moderate E, where these samples are characterized by a negative nonohmicity (dσ(0, E)/dE < 0), the ratio σ(H, E)/σ(0, E) > 1 (negative magnetoresistance). With increasing E, these inequalities are simultaneously reversed (positive nonohmicity and positive magnetoresistance). It is suggested that both negative and positive nonohmicities are due to electron transitions in electric fields from impurity ground states to states in the Mott-Hubbard gap.
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Gol'tsman, G., Semenov, A., Smirnov, K., & Voronov, B. (2001). Background limited quantum superconducting detector for submillimeter wavelengths. In Proc. 12th Int. Symp. Space Terahertz Technol. (pp. 469–475).
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Shelkovnikov, A., Grain, C., Nguyen, C. T., Butcher, R. J., Amy-Klein, A., & Chardonnet, C. (2001). 500-Hz two-photon Ramsey fringes with a SF6 beam: towards a new frequency standard in the 30-THz spectral region. Appl. Phys. B: Lasers and Optics, 73, 93–98.
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Semenov, A., Goltsman, G., & Korneev, A. (2001). Quantum detection by current carrying superconducting film. Phys. C: Supercond., 351(4), 349–356.
Abstract: We describe a novel quantum detection mechanism in the superconducting film carrying supercurrent. The mechanism incorporates growing normal domain and breaking of superconductivity by the bias current. A single photon absorbed in the film creates transient normal spot that causes redistribution of the current and, consequently, increase of the current density in superconducting areas. When the current density exceeds the critical value, the film switches into resistive state and generates the voltage pulse. Analysis shows that a submicron-wide film of conventional low temperature superconductor operated in liquid helium may detect single far-infrared photon. The amplitude and duration of the voltage pulse are in the millivolt and picosecond range, respectively. The quantitative model is presented that allows simulation of the detector utilizing this detection mechanism.
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Boreman, G. D. (2001). A Users guide to IR detectors. In Proc. SPIE (Vol. 4420, pp. 79–90).
Abstract: This paper will guide the first-time user toward proper selection and use of IR detectors for applications in industrial inspection, process control, and laser measurements.
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Codreanu, I., & Boreman, G. D. (2001). Infrared microstrip dipole antennas. Microw Opt Technol Lett, 29(6), 381–383.
Abstract: Abstract 10.1002/mop.1184.abs We report on the successful use of niobium microbolometers coupled to microstrip dipole antennas for the detection of midinfrared radiation. Measurements of the detector response versus antenna length performed at the 10.6 μm wavelength allowed us to identify the first three current-wave resonances along the antenna arms. The detector response was also measured as a function of the radiation wavelength in the 911 μm spectral domain. Excellent agreement between the experimental results and finite-difference time-domain (FDTD) predictions was obtained.
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Puscasu, I., & Boreman, G. D. (2001). Theoretical and experimental analysis of transmission and enchanced absorption of frequency selective surfaces in the infrared. In Proc. SPIE (Vol. 4293, pp. 185–190).
Abstract: A comparative study between theory and experiment is presented for transmission through lossy frequency selective surfaces (FSSs) on silicon in the 2 – 15 micrometer range. Important parameters controlling the resonance shape and location are identified: dipole length, spacing, impedance, and dielectric surroundings. Their separate influence is exhibited. The primary resonance mechanism of FSSs is the resonance of the individual metallic patches. There is no discernable resonance arising from a feed-coupled configuration. The real part of the element's impedance controls the minimum value of transmission, while scarcely affecting its location. Varying the imaginary part shifts the location of resonance, while only slightly changing the minimum value of transmission. With such fine-tuning, it is possible to make a good fit between theory and experiment near the dipole resonance on any sample. A fixed choice of impedance can provide a reasonable fit to all samples fabricated under the same conditions. The dielectric surroundings change the resonance wavelength of the FSS compared to its value in air. The presence of FSS on the substrate increases the absorptivity/emissivity of the surface in a resonant way. Such enhancement is shown for dipole and cross arrays at several wavelengths.
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Verevkin, A., Williams, C., Gol’tsman, G. N., Sobolewski, R., & Gilbert, G. (2001). Single-photon superconducting detectors for practical high-speed quantum cryptography. Optical Society of America.
Abstract: We have developed an ultrafast superconducting single-photon detector with negligible dark counting rate. The detector is based on an ultrathin, submicron-wide NbN meander-type stripe and can detect individual photons in the visible to near-infrared wavelength range at a rate of at least 10 Gb/s. The above counting rate allows us to implement the NbN device to unconditionally secret quantum key distRochester, New Yorkribution in a practical, high-speed system using real-time Vernam enciphering.
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Gol’tsman, G., Okunev, O., Chulkova, G., Lipatov, A., Dzardanov, A., Smirnov, K., et al. (2001). Fabrication and properties of an ultrafast NbN hot-electron single-photon detector. IEEE Trans. Appl. Supercond., 11(1), 574–577.
Abstract: A new type of ultra-high-speed single-photon counter for visible and near-infrared wavebands based on an ultrathin NbN hot-electron photodetector (HEP) has been developed. The detector consists of a very narrow superconducting stripe, biased close to its critical current. An incoming photon absorbed by the stripe produces a resistive hotspot and causes an increase in the film’s supercurrent density above the critical value, leading to temporary formation of a resistive barrier across the device and an easily measurable voltage pulse. Our NbN HEP is an ultrafast (estimated response time is 30 ps; registered time, due to apparatus limitations, is 150 ps), frequency unselective device with very large intrinsic gain and negligible dark counts. We have observed sequences of output pulses, interpreted as single-photon events for very weak laser beams with wavelengths ranging from 0.5 /spl mu/m to 2.1 /spl mu/m and the signal-to-noise ratio of about 30 dB.
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Verevkin, A., Xu, Y., Zheng, X., Williams, C., Sobolewski, R., Okunev, O., et al. (2001). Superconducting NbN-based ultrafast hot-electron single-photon detector for infrared range. In Proc. 12th Int. Symp. Space Terahertz Technol. (pp. 462–468).
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