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Trabesinger, A. (2009). Quantum mechanics: Shaken foundations. Nat. Phys., 5(12), 863.
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Benford, D., Moseley, H., & Zmuidzinas, J. (2009). Direct detectors for the Einstein inflation probe. In J. Phys.: Conf. Ser. (Vol. 155, 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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Ovchinnikov, Y. N., & Varlamov, A. A. (2009). Fluctuation-dissipative phenomena in a narrow superconducting channel carrying current below critical. arXiv, 0910.2659v1, 1–4.
Abstract: The theory of current transport in a narrow superconducting channel accounting for thermal fluctuations is developed. These fluctuations result in the appearance of small but finite dissipation in the sample. The value of corresponding voltage is found as the function of temperature (close to transition temperature) and arbitrary bias current. It is demonstrated that the value of the activation energy (exponential factor in the Arrenius law) when current approaches to the critical one is proportional to (1-J/Jc)^(5/4). This result is in concordance with the one for the affine phenomenon of the Josephson current decay due to the thermal phase fluctuations, where the activation energy proportional (1-J/J_c)^(3/2)(the difference in the exponents is related to the additional current dependence of the order parameter). Found dependence of the activation energy on current explains the enormous discrepancy between the theoretically predicted before and the experimentally observed broadening of the resistive transition.
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Khosropanah P., Baryshev A., Zhang W., Jellema W., Hovenier J.N., Gao G.R., et al. (2009). Phase-locking of a 2.7-THz quantum cascade laser to a microwave reference. Optics Letters, 34, 2958–2960.
Abstract: We demonstrate the phase locking of a 2.7 THz metal–metal waveguide quantum cascade laser (QCL) to an external microwave signal. The reference is the 15th harmonic, generated by a semiconductor superlattice nonlinear device, of a signal at 182 GHz, which itself is generated by a multiplier chain (X12) from a
microwave synthesizer at ~ 15 GHz. Both laser and reference radiations are coupled into a bolometer mixer, resulting in a beat signal, which is fed into a phase-lock loop. The spectral analysis of the beat signal con-firms that the QCL is phase locked. This result opens the possibility to extend heterodyne interferometers into the far-infrared range.
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Ozhegov, R. V., Smirnov, A. V., Vakhtomin, Y. B., Smirnov, K. V., Divochiy, A. V., & Goltsman, G. N. (2009). Ultrafast superconducting bolometer receivers for terahertz applications. In Proc. PIERS (867). 777 Concord Avenue, Suite 207 Cambridge, MA 02138: The Electromagnetics Academy.
Abstract: The research by the group of Moscow State Pedagogical University into the hot-electron phenomena in thin superconducting films has led to the development of new types of detectors and their use both in fundamental and applied studies. In this paper, we present the results of testing the terahertz HEB receiver systems based on ultrathin (∼ 4 nm) NbN and MoRe detectors with a response time of 50 ps and 1 ns, respectively. We have developed three types of devices which differ in the way a terahertz signal is coupled to the detector and cover the following ranges: 0.3–3 THz, 0.1–30 THz and 25–70 THz. In the case of the receiving system optimized for 0.3–3 THz, the sensitive element (a strip of asuperconductor with planar dimensions of 0.2μm (length) by 1.7μm (width)) was integrated witha planar broadband log-spiral antenna. For additional focusing ofthe incident radiation a silicon hyperhemispherical lens was used. For the 0.1–30 THz receivingsystem, the sensitive element was patterned as parallel strips(2μm wide each) filling an area of 500×500μm2with a filling factor of 0.5. In the receivingsystem of this type we used direct coupling of the incident radiation to the sensitive element. Inthe 25–70 THz range (detector type 2/2a in Table 1) we used a square-shaped superconductingdetector with planar dimensions of 10×10μm2. Incident radiation was coupled to the detectorwith the use of a germanium hyperhemispherical lens.The response time of the above receiving systems is determined by the cooling rate of the hotelectrons in the film. That depends on the electron-phonon interaction time, which is less forultrathin NbN than in MoRe.
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