Single-shot measurement of THz pulses**Project supported by the National Natural Science Foundation of China (Grant Nos. 61427814 and 61575161), the National Key Research and Development Program of China (Grant No. 2017YFA0701005), and the Natural Science Foundation of Shaanxi Province, China (Grant No. 2019JZ-04).

Abstract

Terahertz (THz) waves have shown a broad prospect in the analysis of some dielectric materials because of their special properties. For the ultrafast irreversible processes, the THz single-shot measurement is a good choice. In this paper, a single-shot system is investigated, where a pump beam is used to generate THz pulses with high electrical field by optical rectification in LiNbO3, the probe beam with wavefront tilted by a blazed grating is used for single-shot measurement. The time window is up to 90 ps, the signal to noise ratio is 2000 : 1, the spectrum covers from 0.1 THz to about 2.0 THz, and the spectral resolution is 0.011 THz. The single-shot measurement result agrees well with that of a traditional electrical-optic sampling method.