A configuration for an optical pumped monochromatic terahertz (THz) source operating in a high repetition rate is developed and based on a resonant parametric process within a Fabry–Perot microcavity. Comprehensive analysis of the spectral selection, cavity phase matching, energy-conversion dynamic, and input–output characteristics is provided. Calculations are performed on a Tm3_-doped fiber laser pumped GaAs sheet. It is indicated that a pump threshold can be scaled down by injection seeding of the signal wave. Efficient THz wave generation (mW level average power) under relatively low pump peak power (65 kW) is predicted.

This work was published on Journal of the Optical Society of America B,2018,35(1):68-72. titled Low-threshold terahertz-wave generation based on a cavity phase-matched parametric process in a Fabry–Perot microresonator.