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Cao, Q., Yoon, S. F., Tong, C. Z., Ngo, C. Y., Liu, C. Y., Wang, R., et al. (2009). Two-state competition in 1.3 μm multilayer InAs/InGaAs quantum dot lasers. Appl. Phys. Lett., 95(19), 3.
Abstract: The competition of ground state (GS) and excited state (ES) is investigated from the as-grown and thermally annealed 1.3 μm ten-layer p-doped InAs/GaAs quantum dot (QD) lasers. The modal gain competition between GS and ES are measured and analyzed around the ES threshold characteristics. Our results show that two-state competition is more significant in devices with short cavity length operating at high temperature. By comparing the as-grown and annealed devices, we demonstrate enhanced GS and suppressed ES lasing from the QD laser annealed at 600 °C for 15 s.
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Gaggero, A., Nejad, S. J., Marsili, F., Mattioli, F., Leoni, R., Bitauld, D., et al. (2010). Nanowire superconducting single-photon detectors on GaAs for integrated quantum photonic applications. Appl. Phys. Lett., 97(15), 3.
Abstract: We demonstrate efficient nanowire superconducting single photon detectors (SSPDs) based on NbN thin films grown on GaAs. NbN films ranging from 3 to 5 nm in thickness have been deposited by dc magnetron sputtering on GaAs substrates at 350 °C. These films show superconducting properties comparable to similar films grown on sapphire and MgO. In order to demonstrate the potential for monolithic integration, SSPDs were fabricated and measured on GaAs/AlAs Bragg mirrors, showing a clear cavity enhancement, with a peak quantum efficiency of 18.3% at λ = 1300 nm and T = 4.2 K.
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Yates, S. J. C., Baryshev, A. M., Baselmans, J. J. A., Klein, B., & Güsten, R. (2009). Fast Fourier transform spectrometer readout for large arrays of microwave kinetic inductance detectors. Appl. Phys. Lett., 95(4), 3.
Abstract: Microwave kinetic inductance detectors have great potential for large, very sensitive detector arrays for use in, for example, submillimeter imaging. Being intrinsically readout in the frequency domain, they are particularly suited for frequency domain multiplexing allowing ~1000 s of devices to be readout with one pair of coaxial cables. However, this moves the complexity of the detector from the cryogenics to the warm electronics. We present here the concept and experimental demonstration of the use of fast Fourier transform spectrometer readout, showing no deterioration of the noise performance compared to the low noise analog mixing while allowing high multiplexing ratios.
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Hoevers, H. F. C., Bento, A. C., Bruijn, M. P., Gottardi, L., Korevaar, M. A. N., Mels, W. A., et al. (2000). Thermal fluctuation noise in a voltage biased superconducting transition edge thermometer. Appl. Phys. Lett., 77(26), 4421–4424.
Abstract: The current noise at the output of a microcalorimeter with a voltage biased superconducting transition edge thermometer is studied in detail. In addition to the two well-known noise sources: thermal fluctuation noise from the heat link to the bath and Johnson noise from the resistive thermometer, a third noise source strongly correlated with the steepness of the thermometer is required to fit the measured noise spectra. Thermal fluctuation noise, originating in the thermometer itself, fully explains the additional noise. A simple model provides quantitative agreement between the observed and calculated noise spectra for all bias points in the superconducting transition.
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Burke, P. J., Schoelkopf, R. J., Prober, D. E., Skalare, A., Karasik, B. S., Gaidis, M. C., et al. (1998). Spectrum of thermal fluctuation noise in diffusion and phonon cooled hot-electron mixers. Appl. Phys. Lett., 72(12), 1516–1518.
Abstract: A systematic study of the intermediate frequency noise bandwidth of Nb thin-film superconducting hot-electron bolometers is presented. We have measured the spectrum of the output noise as well as the conversion efficiency over a very broad intermediate frequency range (from 0.1 to 7.5 GHz) for devices varying in length from 0.08 μm to 3 μm. Local oscillator and rf signals from 8 to 40 GHz were used. For a device of a given length, the spectrum of the output noise and the conversion efficiency behave similarly for intermediate frequencies less than the gain bandwidth, in accordance with a simple thermal model for both the mixing and thermal fluctuation noise. For higher intermediate frequencies the conversion efficiency decreases; in contrast, the noise decreases but has a second contribution which dominates at higher frequency. The noise bandwidth is larger than the gain bandwidth, and the mixer noise is low, between 120 and 530 K (double side band).
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