|
Karasik, B. S., & Elantiev, A. I. (1996). Noise temperature limit of a superconducting hot-electron bolometer mixer. Appl. Phys. Lett., 68(6), 853–855.
|
|
|
Miao, W., Zhang, W., Zhong, J. Q., Shi, S. C., Delorme, Y., Lefevre, R., et al. (2014). Non-uniform absorption of terahertz radiation on superconducting hot electron bolometer microbridges. <ef><bf><bc>Appl. Phys. Lett., 104, 052605(1–4).
Abstract: We interpret the experimental observation of a frequency-dependence of superconducting hot electron bolometer (HEB) mixers by taking into account the non-uniform absorption of the terahertz radiation on the superconducting HEB microbridge. The radiation absorption is assumed to be proportional to the local surface resistance of the HEB microbridge, which is computed using the Mattis-Bardeen theory. With this assumption the dc and mixing characteristics of a superconducting niobium-nitride (NbN) HEB device have been modeled at frequencies below and above the equilibrium gap frequency of the NbN film.
|
|
|
Lindgren, M., Zorin, M. A., Trifonov, V., Danerud, M., Winkler, D., Karasik, B. S., et al. (1994). Optical mixing in a patterned YBa2Cu3O7-δ thin film. Appl. Phys. Lett., 65(26), 3398–3400.
Abstract: Mixing of 1.56 µm infrared radiation from two lasers in a high quality YBa2Cu3O7-δ thin film, patterned to parallel strips, was demonstrated. A mixer bandwidth of 18 GHz, limited by the measurement system, was obtained. A model based on nonequilibrium electron heating gives a good fit to the data and predicts an intrinsic mixer bandwidth in excess of 100 GHz, operating in the whole infrared spectrum. Reduction of bolometric effects and ways to decrease the conversion loss of the mixer is discussed. The minimum conversion loss is expected to be ~10 dB.
|
|
|
Bennett, D. A., Schmidt, D. R., Swetz, D. S., & Ullom, J. N. (2014). Phase-slip lines as a resistance mechanism in transition-edge sensors. Appl. Phys. Lett., 104, 042602.
Abstract: The fundamental mechanism of resistance in voltage-biased superconducting films is poorly understood despite its importance as the basis of transition-edge sensors (TESs). TESs are utilized in state-of-the-art microbolometers and microcalorimeters covering a wide range of energies and applications. We present a model for the resistance of a TES based on phase-slip lines (PSLs) and compare the model to data. One of the model's predictions, discrete changes in the number of PSLs, is a possible explanation for the observed switching between discrete current states in localized regions of bias.
|
|
|
Fedorov, G., Kardakova, A., Gayduchenko, I., Charayev, I., Voronov, B. M., Finkel, M., et al. (2013). Photothermoelectric response in asymmetric carbon nanotube devices exposed to sub-terahertz radiation. Appl. Phys. Lett., 103(18), 181121 (1 to 5).
Abstract: We report on the voltage response of carbon nanotube devices to sub-terahertz (THz) radiation. The devices contain carbon nanotubes (CNTs), which are over their length partially suspended and partially Van der Waals bonded to a SiO2 substrate, causing a difference in thermal contact. We observe a DC voltage upon exposure to 140 GHz radiation. Based on the observed gate voltage and power dependence, at different temperatures, we argue that the observed signal is both thermal and photovoltaic. The room temperature responsivity in the microwave to THz range exceeds that of CNT based devices reported before. Authors thank Professor P. Barbara for providing the catalyst for CNT growth and Dr. N. Chumakov and V. Rylkov for stimulating discussions. The work was supported by the RFBR (Grant No. 12-02-01291-a) and by the Ministry of Education and Science of the Russian Federation (Contract No. 14.B25.31.0007). G.F. acknowledges support of the RFBR grant 12-02-01005-a.
|
|