Characterization of Response Time of Superconducting NbN Hot Electron Bolometer Mixers

Response time of a Superconducting Hot Electron Bolometer (HEB) mixers is a critical parameter, and significantly affects the intermediate frequency (IF) gain bandwidth. In this study, we investigated the effects of temperature and bias voltage on the response time. Response time of superconducting niobium nitride (NbN) HEB mixers were measured by using the pumpprobe technique at temperatures of 5 K, 7 K, and 9 K with different bias voltages. The measured response time ranged from 50 to 80 ps and decreased with increasing temperature and bias voltage. This approach provides a more comprehensive understanding of the thermal transport mechanisms in superconducting HEB mixers, which can ultimately lead to improved performance and properties of the HEB mixers.