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Kerman, A. J., Yang, J. K. W., Molnar, R. J., Dauler, E. A., & Berggren, K. K. (2009). Electrothermal feedback in superconducting nanowire single-photon detectors. Phys. Rev. B, 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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Beck, M., Klammer, M., Lang, S., Leiderer, P., Kabanov, V. V., Gol'tsman, G. N., et al. (2011). Energy-gap dynamics of superconducting NbN thin films studied by time-resolved terahertz spectroscopy. Phys. Rev. Lett., 107(17), 4.
Abstract: Using time-domain terahertz spectroscopy we performed direct studies of the photoinduced suppression and recovery of the superconducting gap in a conventional BCS superconductor NbN. Both processes are found to be strongly temperature and excitation density dependent. The analysis of the data with the established phenomenological Rothwarf-Taylor model enabled us to determine the bare quasiparticle recombination rate, the Cooper pair-breaking rate and the electron-phonon coupling constant, λ=1.1±0.1, which is in excellent agreement with theoretical estimates.
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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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Ciulin, V., Carter, S. G., & Sherwin, M. S. (2004). Terahertz optical mixing in biased GaAs single quantum wells. Phys. Rev. B, 70(11), 115312–(1–6).
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Su, M. Y., Carter, S. G., & Sherwin, M. S. (2003). Strong-field terahertz optical mixing in excitons. Phys. Rev. B, 67(12).
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