Design considerations of an infrared spectrometer based on difference–frequency generation in AgGaSe_2

Abstract

The availability of new nonlinear optical materials such as AgGaS(2) and AgGaSe(2) and improvements in compact, tunable, pulsed and continuous-wave (cw) solid-state pump lasers now make it possible to generate tunable, infrared narrow-band coherent radiation over a wide wavelength range (4-18 µm) by means of difference-frequency generation (DFG). This article describes the wavelength and outputpower characteristics of a tunable infrared source based on AgGaSe(2) and certain proven cw near-infrared pump sources for application to high-resolution spectroscopy.