|
|
Finkel, M., Thierschmann, H., Galatro, L., Katan, A. J., Thoen, D. J., de Visser, P. J., et al. (2017). Performance of THz components based on microstrip PECVD SiNx technology. IEEE Trans. THz Sci. Technol., 7(6), 765–771.
Abstract: We present a performance analysis of passive THz components based on Microstrip transmission lines with a 2-μmthin plasma-enhanced chemical vapor deposition grown silicon nitride (PECVD SiNX) dielectric layer. A set of thru-reflect-line calibration structures is used for basic transmission line characterizations. We obtain losses of 9 dB/mm at 300 GHz. Branchline hybrid couplers are realized that exhibit 2.5-dB insertion loss, 1-dB amplitude imbalance, and -26-dB isolation, in agreement with simulations. We use the measured center frequency to determine the dielectric constant of the PECVD SiN x , which yields 5.9. We estimate the wafer-to-wafer variations to be of the order of 1%. Directional couplers are presented which exhibit -12-dB transmission to the coupled port and -26 dB to the isolated port. For transmission lines with 5-μm-thin silicon nitride (SiN x ), we observe losses below 4 dB/mm. The thin SiN x dielectric membrane makes the THz components compatible with scanning probe microscopy cantilevers allowing the application of this technology in on-chip circuits of a THz near-field microscope.
|
|
|
|
Kardakova, A. I., Coumou, P. C. J. J., Finkel, M. I., Morozov, D. V., An, P. P., Goltsman, G. N., et al. (2015). Electron–phonon energy relaxation time in thin strongly disordered titanium nitride films. IEEE Trans. Appl. Supercond., 25(3), 1–4.
Abstract: We have measured the energy relaxation times from the electron bath to the phonon bath in strongly disordered TiN films grown by atomic layer deposition. The measured values of τ eph vary from 12 to 91 ns. Over a temperature range from 3.4 to 1.7 K, they follow T -3 temperature dependence, which are consistent with values of τ eph reported previously for sputtered TiN films. For the most disordered film, with an effective elastic mean free path of 0.35 nm, we find a faster relaxation and a stronger temperature dependence, which may be an additional indication of the influence of strong disorder on a superconductor.
|
|
|
|
Кардакова, А. И., Финкель, М. И., Морозов, Д. В., Ковалюк, В. В., Ан, П. П., & Гольцман, Г. Н. (2014). Время электрон-фононного взаимодействия в сверхпроводниковых пленках нитрида титана. In Труды XVIII международного симпозиума «Нанофизика и наноэлектроника» (Vol. 1, pp. 47–48).
Abstract: Определены времена электрон-фононного взаимодействия в тонких сверхпроводниковых пленках нитрида титана. Измеренные значения τ_eph находятся в диапазоне от 5.5 нс до 88 нс при температурах 4,2 К и 1,7 К, соответственно, и соответствуют температурной зависимости Т^-3.
|
|
|
|
Gol'tsman, G., Semenov, A., Smirnov, K., & Voronov, B. (2001). Background limited quantum superconducting detector for submillimeter wavelengths. In Proc. 12th Int. Symp. Space Terahertz Technol. (pp. 469–475).
|
|
|
|
Nikoghosyan, A. S., Martirosyan, R. M., Hakhoumian, A. A., Makaryan, A. H., Tadevosyan, V. R., Goltsman, G. N., et al. (2018). Effect of absorption on the efficiency of THz radiation generation in a nonlinear crystal placed into a waveguide. Armenian J. Phys., 11(4), 257–262.
Abstract: The effect of THz radiation absorption on the efficiency of generation of coherent THz radiation in a nonlinear optical crystal placed into a metal rectangular waveguide is studied. The efficiency of the nonlinear conversion of optical laser radiation to the THz band is also a function of the phase-matching (PM) condition inside the nonlinear crystal. The method of partial filling of a metal waveguide with a nonlinear optical crystal is used to ensure phase matching. Phase matching was obtained by the proper choice of the thickness of the nonlinear crystal, namely the degree of partial filling of the waveguide. We have studied the THz radiation attenuation caused by the losses in both the metal walls of the waveguide and in the crystal, taking into account the dimension of the cross section of the waveguide, the degree of partial filling and its dielectric constant.
|
|
