Investigation of temperature dependence of microwave-induced characteristics of a NbN Josephson junction array

To investigate the temperature dependence of microwave-induced characteristics of a NbN Josephson junction array, the surface resistance, R_s, of NbN films was measured using the dielectric resonator method at 22 GHz and temperatures from 5.8 K to 14.8 K. From the measured R_s values, the attenuation of 16 GHz microwaves in a NbN coplanar waveguide was calculated and constant-voltage-step amplitude for a NbN junction array biased with a DC current and 16 GHz microwaves was calculated as a function of temperature, resulting in a theoretical temperature dependence of constant-voltage-step amplitude.