Reaching higher speed and sensitivity with single-THz-pulse and single-THz-photon detection

Real-time detection of terahertz (THz) radiation has the potential to unlock scientific discoveries in studies of fast and non-reproducible phenomena. Additionally, detection schemes able to resolve single THz photons are essential to enable a new range of quantum applications. Here, we demonstrate two distinct rapid and highly-sensitive approaches to the detection of pulsed THz radiation: i) a single-shot measurement technique which employs chirped-pulse spectral encoding and a dispersive Fourier transform method for time-resolved THz spectroscopy at rates up to 1.1 MHz; and ii) a single-THz-photon detection technique based on frequency upconversion and single-photon counting technology capable of zeptojoule THz detection. These innovative detection schemes pave the way for real-time monitoring of irreversible phenomena in organic materials, sensitive wireless signal detection, and highly non-degenerate quantum ghost imaging applications.