Real-time Continuous Wave Terahertz Spectroscopy with 2 THz Bandwidth

Until now, real-time acquisition of terahertz (THz) spectra has been an unique feature of time-domain spectroscopy (TDS) systems. However, fast acquisition of broadband THz signals can be a strength of continuous-wave (cw) THz as well, when a fast frequency tunable laser source is used. In this paper, we present a new continuous wave THz spectrometer capable of acquiring 2 THz-wide spectra with 1 GHz resolution at 8 Hz continuous update rate. To our knowledge, this is the first demonstration of a phase-sensitive cw THz spectrometer able to perform broadband acquisition in real-time.