High-Dynamic Range Broadband Terahertz Time-Domain Spectrometer Based on Organic Crystal MNA

Abstract

We present a high power and broadband THz-TDS setup utilizing the nonlinear organic crystal MNA both as emitter and detector. The THz source is based on optical rectification of near infra-red laser pulses at a central wavelength of 1036 nm from a commercial, high-power Yb-based laser system and reaches a high THz average power of 11 mW at a repetition rate of 100 kHz and a broad and smooth bandwidth of more than 9 THz. The conversion efficiency is high (0.13%) in spite of the high excitation average power of 8 W. We validate the high dynamic range and reliability of the source for applications in linear spectroscopy by measuring the broadband THz properties of chi(2) nonlinear crystals up to 8 THz. This new high-repetition rate source is very promising for ultra-broadband THz spectroscopy at high dynamic range and/or reduced measurement times.