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Karpowicz N, Lu X, Zhang X-C. Terahertz gas photonics. J. Modern Opt.. 2009;56(10):1137–50.
Abstract: The underlying physics of the generation and detection of terahertz (THz) waves in gases are described. The THz wave generation process takes place in two steps: asymmetric gas ionization by two-frequency laser fields, followed by interaction of the ionized electron wave packets with the surrounding medium, producing an intense ‘echo' with tunable spectral content. In order to clarify the physical picture at the moment of ionization, the laser–atom interaction is treated through solution of the time-dependent Schrödinger equation, yielding an ab initio understanding of the release of the electron wave packets. The second step, where the electrons interact with the surrounding plasma is treated analytically. The resulting pressure dependence of the THz radiation is explored in detail. The THz wave detection process is shown to be the result of four-wave mixing, leading to analytical expressions of the signal obtained which allow for improved optimization of systems that exploit these effects.
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Kerman AJ, Yang JKW, Molnar RJ, Dauler EA, Berggren KK. Electrothermal feedback in superconducting nanowire single-photon detectors. Phys Rev B. 2009;79(10):4.
Abstract: We investigate the role of electrothermal feedback in the operation of superconducting nanowire single-photon detectors (SNSPDs). It is found that the desired mode of operation for SNSPDs is only achieved if this feedback is unstable, which happens naturally through the slow electrical response associated with their relatively large kinetic inductance. If this response is sped up in an effort to increase the device count rate, the electrothermal feedback becomes stable and results in an effect known as latching, where the device is locked in a resistive state and can no longer detect photons. We present a set of experiments which elucidate this effect and a simple model which quantitatively explains the results.
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Minaeva O, Bonato C, Saleh BEA, Simon DS, Sergienko AV. Odd- and even-order dispersion cancellation in quantum interferometry. Phys Rev Lett. 2009;102(10):4.
Abstract: We describe a novel effect involving odd-order dispersion cancellation. We demonstrate that odd- and even-order dispersion cancellation may be obtained in different regions of a single quantum interferogram using frequency-anticorrelated entangled photons and a new type of quantum interferometer. This offers new opportunities for quantum communication and metrology in dispersive media.
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Meledin D, Pavolotsky A, Desmaris V, Lapkin I, Risacher C, Perez V, et al. A 1.3-THz balanced waveguide HEB mixer for the APEX telescope. IEEE Trans. Microw. Theory Techn.. 2009;57(1):89–98.
Abstract: In this paper, we report about the development, fabrication, and characterization of a balanced waveguide hot electron bolometer (HEB) receiver for the Atacama Pathfinder EXperiment telescope covering the frequency band of 1.25–1.39 THz. The receiver uses a quadrature balanced scheme and two HEB mixers, fabricated from 4- to 5-nm-thick NbN film deposited on crystalline quartz substrate with an MgO buffer layer in between. We employed a novel micromachining method to produce all-metal waveguide parts at submicrometer accuracy (the main-mode waveguide dimensions are 90×180 μm). We present details on the mixer design and measurement results, including receiver noise performance, stability and “first-light†at the telescope site. The receiver yields a double-sideband noise temperature averaged over the RF band below 1200 K, and outstanding stability with a spectroscopic Allan time more than 200 s.
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Ryabchun S, Tong C-YE, Blundell R, Gol'tsman G. Stabilization scheme for hot-electron bolometer receivers using microwave radiation. IEEE Trans Appl Supercond. 2009;19(1):14–9.
Abstract: We present the results of a stabilization scheme for terahertz receivers based on NbN hot-electron bolometer (HEB) mixers that uses microwave radiation with a frequency much lower than the gap frequency of NbN to compensate for mixer current fluctuations. A feedback control loop, which actively controls the power level of the injected microwave radiation, has successfully been implemented to stabilize the operating point of the HEB mixer. This allows us to increase the receiver Allan time to 10 s and also improve the temperature resolution of the receiver by about 30% in the total power mode of operation.
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Benford D, Moseley H, Zmuidzinas J. Direct detectors for the Einstein inflation probe. In: J. Phys.: Conf. Ser. Vol 155.; 2009. 012001 (1 to 49).
Abstract: Here we review the principles of operation, history, present status, and future prospects for the primary candidate detectors for Cosmic Microwave Background (CMB) polarization studies. The three detector types we will discuss are semiconductor-based bolometers, superconducting transition edge sensor (TES) bolometer, and Microwave Kinetic Inductance Detectors (MKIDs). All of these detector types can provide the sensitivity to permit background-limited measurements of the CMB, but the ultimate selection of detectors will be largely determined by the ease of production and reliability of large arrays of such detectors. This paper describes the present state of development of these detectors, efforts to integrate them into large arrays, and the detector system developments necessary to enable a space CMB polarization mission.
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Anosov AA, Barabanenkov YN, Kazanskii AS, Less YA, Sharakshane AS. The inverse problem of acoustothermography with correlation reception of thermal acoustic radiation. Acoust. Phys.. 2009;55(1):114–9.
Abstract: For the one-dimensional inverse problem of acoustothermography with correlation reception of thermal acoustic radiation, an integral equation is presented and experimentally verified. A method of solving the inverse problem is proposed. The method is based on combining the correlation functions of thermal acoustic radiation that were obtained for different distances between the receivers.
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Wild W, Kardashev NS, Likhachev SF, Babakin NG, Arkhipov VY, Vinogradov IS, et al. Millimetron—a large Russian-European submillimeter space observatory. Exp Astron. 2009;23(1):221–44.
Abstract: Millimetron is a Russian-led 12 m diameter submillimeter and far-infrared space observatory which is included in the Space Plan of the Russian Federation for launch around 2017. With its large collecting area and state-of-the-art receivers, it will enable unique science and allow at least one order of magnitude improvement with respect to the Herschel Space Observatory. Millimetron will be operated in two basic observing modes: as a single-dish observatory, and as an element of a ground-space very long baseline interferometry (VLBI) system. As single-dish, angular resolutions on the order of 3 to 12 arc sec will be achieved and spectral resolutions of up to a million employing heterodyne techniques. As VLBI antenna, the chosen elliptical orbit will provide extremely large VLBI baselines (beyond 300,000 km) resulting in micro-arc second angular resolution.
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Treuttel J, Thomas B, Maestrini A, Wang H, Alderman B, Siles JV, et al. A 380 GHz sub-harmonic mixer using MMIC foundry based Schottky diodes transferred onto quartz substrate. In: Proc. 20th Int. Symp. Space Terahertz Technol. Charlottesville, Virginia, USA; 2009.
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Минаева ОВ. Быстродействующий однофотонный детектор на основе тонкой сверхпроводниковой пленки NbN [Ph.D. thesis].; 2009.
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