Hot Electron Y-Ba-Cu-O Bolometer Heterodyne Mixers: Stand-Off Target Passive Detection Performance Modeling

A hot spot model for superconducting Y-Ba-CuO hot electron bolometer (HEB) mixers has been applied to evaluate stand-off THz detection. The HEB performance has been simulated in terms of double sideband noise temperature T-DSB and conversion gain G. For a device constriction of length = width = 400 nm and thickness = 35 nm, we obtained, e.g., T-DSB = 1010 K and G = -6.1 dB at 2.5 THz (12.5 mu W local oscillator power). A stand-off passive detection scheme performance is discussed, for a 4 GHz mixer instantaneous bandwidth, in terms of achievable target differential temperature resolution, spatial resolution, atmospheric absorption and humidity conditions.