Guided-wave difference-frequency sources for infrared spectroscopy

摘要

Reported are design, performance, and spectroscopic application of an infrared source based on difference-frequency mixing of diode lasers. The source employs an annealed proton exchanged channel waveguide in periodically poled lithium niobate and operates in the 3.2-3.9μm wavelength region at room temperature. Device efficiency of up to 4 %-W~(-1) and output power of up to 145μW were obtained. Spatial and spectral characteristics of the output beam were examined. High-resolution spectroscopy and detection of several trace gases were performed.