Trace-gas detection based on the temperature-tuning periodically poled MgO: LiNbO_3 optical parametric oscillator

摘要

We report on the use of the temperature-tuned optical parametric oscillator for trace gas detection. A synchronization trace gas detection system was designed and demonstrated, in which the measuring errors caused by the instability of the OPO could be greatly reduced. The trace gas detection system was based on a periodically poled MgO-doped LiNbO_3 optical parametric oscillator (OPO) which was pumped by a diode-pumped passively Q-switched Nd:GdVO_4rnlaser. The OPO could produce wavelength-tunable signal output through changing the crystal temperature and the grating periods. The usefulness of the trace gas detection system for spectroscopy was demonstrated by directlyrnmeasuring the photon absorption spectrum of the methane and acetylene gas cells.