arXiv:2211.09422 · Optics Express
THz optical beat-note detection with a fast superconducting hot electron bolometer operating up to 31 GHz
G. Torrioli, Andres Forrer, Mattias Beck, P. Carelli, F. Chiarello, Jérôme Faist, Alessandro Gaggero, E. Giovine, F. Martini, Urban Senica, Roberto Leoni, Giacomo Scalari, Sara Cibella
Abstract
We study the performance of a hot-electron bolometer (HEB) operating at THz frequencies based on superconducting niobium nitride films. We report on the voltage response of the detector over a large electrical detection bandwidth carried out with different THz sources. We show that the impulse response of the fully packaged HEB at 7.5 K has a 3 dB cutoff around 2 GHz. Remarkably, detection capability is still observed above 30 GHz in an heterodyne beating experiment using a THz quantum cascade laser frequency comb. Additionally, the HEB sensitivity has been evaluated and an optical noise equivalent power NEP of 0.8 pW/√ H z has been measured at 1 MHz.