We study the performance of an 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 optical 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 cut-off 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/sqrt(Hz) has been measured at 1 MHz.
@article{arxiv.2211.09422,
title = {THz optical beat-note detection with a fast Hot Electron Bolometer operating up to 31 GHz},
author = {G. Torrioli and A. Forrer and M. Beck and P. Carelli and F. Chiarello and J. Faist and A. Gaggero and E. Giovine and F. Martini and U. Senica and R. Leoni and G. Scalari and S. Cibella},
journal= {arXiv preprint arXiv:2211.09422},
year = {2023}
}