Usadel, K. D. (1970). Generalized diffusion equation for superconducting alloys. Phys. Rev. Lett., 25(8), 507.
Abstract: Eilenberger's transportlike equations for a superconductor of type II can be simplified very much in the dirty limit. In this limit a diffusionlike equation is derived which is the generalization of the de Gennes-Maki theory for dirty superconductors to arbitrary values of the order parameter.
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Shytov, A. V., Levitov, L. S., & Beenakker, C. W. J. (2002). Electromechanical noise in a diffusive conductor. Phys. Rev. Lett., 88(22).
Abstract: Electrons moving in a conductor can transfer momentum to the lattice via collisions with impurities and boundaries, giving rise to a fluctuating mechanical stress tensor. The root-mean-squared momentum transfer per scattering event in a disordered metal (of dimension L greater than the mean free path l and screening length xi) is found to be reduced below the Fermi momentum by a factor of order l/L for shear fluctuations and (xi/L)^2 for pressure fluctuations. The excitation of an elastic bending mode by the shear fluctuations is estimated to fall within current experimental sensitivity for a nanomechanical oscillator.
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Shah, N., Pekker, D., & Goldbart, P. M. (2008). Inherent stochasticity of superconductor-resistor switching behavior in nanowires. Phys. Rev. Lett., 101, 207001(1 to 4).
Abstract: We study the stochastic dynamics of superconductive-resistive switching in hysteretic current-biased superconducting nanowires undergoing phase-slip fluctuations. We evaluate the mean switching time using the master-equation formalism, and hence obtain the distribution of switching currents. We find that as the temperature is reduced this distribution initially broadens; only at lower temperatures does it show the narrowing with cooling naively expected for phase slips that are thermally activated. We also find that although several phase-slip events are generally necessary to induce switching, there is an experimentally accessible regime of temperatures and currents for which just one single phase-slip event is sufficient to induce switching, via the local heating it causes.
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Shah, J., Pinczuk, A., Gossard, A. C., & Wiegmann, W. (1985). Energy-loss rates for hot electrons and holes in GaAs quantum wells. Phys. Rev. Lett., 54, 2045–2048.
Abstract: We report the first direct determination of carrier-energy-loss rates in a semiconductor. These measurements provide fundamental insight into carrier-phonon interactions in semiconductors. Unexpectedly large differences are found in the energy-loss rates for electrons and holes in GaAs/AlGaAs quantum wells. This large difference results from an anomalously low electron-energy-loss rate, which we attribute to the presence of nonequilibrium optical phonons rather than the effects of reduced dimensionality or dynamic screening.
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Novotny, L. (2007). Effective wavelength scaling for optical antennas. Phys. Rev. Lett., 98(26), 266802(1–4).
Abstract: In antenna theory, antenna parameters are directly related to the wavelength λ of incident radiation, but this scaling fails at optical frequencies where metals behave as strongly coupled plasmas. In this Letter we show that antenna designs can be transferred to the optical frequency regime by replacing λ by a linearly scaled effective wavelength λeff=n1+n2λ/λp, with λp being the plasma wavelength and n1, n2 being coefficients that depend on geometry and material properties. It is assumed that the antenna is made of linear segments with radii Râ‰<aa>λ. Optical antennas hold great promise for increasing the efficiency of photovoltaics, light-emitting devices, and optical sensors.
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