Shaha, J., Pinczukb, A., Gossardb, A. C., & Wiegmannb, W. (1985). Hot carrier energy loss rates in GaAs quantum wells: large differences between electrons and holes. Phys. B+C, 134(1-3), 174–178.
Abstract: The first direct and separate determination of the hot electron and hot hole energy loss rates to the lattice shows unexpectedly large differences between electrons and holes in GaAs quantum wells. This large difference results from an anomalously low electron energy loss rate, which we attribute to the presence of non-equilibrium optical phonon rather than the effects of reduced dimensionality or dynamic screening. A model calculation of hot phonon effects is presented.
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Uchiki, H., Kobayashi, T., & Sakaki, H. (1987). Photoluminescence and energyâ€loss rates in GaAs quantum wells under highâ€density excitation. J. Appl. Phys., 62(3), 1010–1016.
Abstract: The timeâ€resolved luminescence spectra from excited conduction subbands in three samples of multiâ€quantumâ€well GaAs/AlxGa1-xAs (x=0.3 and 1) semiconductors with several well widths and barrier heights were obtained under highâ€density excitations by a 30â€ps pulsed laser at 532 nm, which generated electron–hole pairs to the concentration of 1010–1013/cm2 per well per pulse at 77 K. The temperature and the Fermi energy of electron were determined by fitting best the constructed timeâ€resolved spectrum to the observed, and the timeâ€dependent electron energy was obtained by using these parameters. The energyâ€loss rates of hot electrons are at least twice smaller than the calculated ones induced by the electronâ€polar phonon scattering, including the screening effect due to the high carrier density.
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Ryabchun, S., Tong, C. - Y. E., Paine, S., Lobanov, Y., Blundell, R., & Goltsman, G. (2009). Temperature resolution of an HEB receiver at 810 GHz. IEEE Trans. Appl. Supercond., 19(3), 293–296.
Abstract: We present the results of direct measurements of the temperature resolution of an HEB receiver operating at 810 GHz, in both continuum and spectroscopic modes. In the continuum mode, the input of the receiver was switched between black bodies with different physical temperatures. With a system noise temperature of around 1100 K, the receiver was able to resolve loads which differed in temperature by about 1 K over an integration time of 5 seconds. This resolution is significantly worse than the value of 0.07 K given by the radiometer equation. In the spectroscopic mode, a gas cell filled with carbonyl sulphide (OCS) gas was used and the emission line at 813.3537060 GHz was measured using the receiver in conjunction with a digital spectrometer. From the observed spectra, we determined that the measurement uncertainty of the equivalent emission temperature was 2.8 K for an integration time of 0.25 seconds and a spectral resolution of 12 MHz, compared to a 1.4 K temperature resolution given by the radiometer equation. This relative improvement is due to the fact that at short integration times the contribution from 1/f noise and drift are less dominant. In both modes, the temperature resolution was improved by about 40% with the use of a feedback loop which adjusted the level of an injected microwave radiation to maintain a constant operating current of the HEB mixer. This stabilization scheme has proved to be very effective to keep the temperature resolution of the HEB receiver to close to the theoretical value given by the radiometer equation.
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Манова, Н. Н., Корнеева, Ю. П., Корнеев, А. А., Слыш, В., Воронов, Б. М., & Гольцман, Г. Н. (2011). Сверхпроводниковый NbN однофотонный детектор, интегрированный с четвертьволновым резонатором. ПЖТФ, 37(10), 7.
Abstract: Исследована спектральная зависимость квантовой эффективности сверхпроводниковых NbN однофотонных детекторов, интегрированных с оптическими четвертьволновыми резонаторами с использованием диэлектриков Si3N4, SiO2, SiO.
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Tretyakov, I., Ryabchun, S., Finkel, M., Maslennikova, A., Kaurova, N., Lobastova, A., et al. (2011). Low noise and wide bandwidth of NbN hot-electron bolometer mixers. Appl. Phys. Lett., 98, 033507 (1 to 3).
Abstract: We report a record double sideband noise temperature of 600 K (5hν/kB) offered by a NbN hot-electron bolometer receiver at 2.5 THz. Allowing for standing wave effects, this value was found to be constant in the intermediate frequency range 1–7 GHz, which indicates that the mixer has an unprecedentedly large noise bandwidth in excess of 7 GHz. The insight into this is provided by gain bandwidth measurements performed at the superconducting transition. They show that the dependence of the bandwidth on the mixer length follows the model for an HEB mixer with diffusion and phonon cooling of the hot electrons.
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