We report on the improvement of a tunable, high resolution, diode laser-based, difference-frequency spectrometer using an AgGaS2 nonlinear crystal. We use a type-II cut crystal as a part of the improvement compared with a type-I cut, which was used in our preliminary setup. The two tunable laser diodes are operating near λ3 = 778 nm (pump) and λ2 = 842 nm (signal) with a sub-100-kHz linewidth. The high resolution spectrometer is being developed as an alternative to CO2 laser spectrometers in the 9- to 11-μm range. Using a dual-arm cavity to enhance the two radiation powers, and with 35 mW in front of the 778-nm arm and 100 mW in front of the 842-nm arm, about 70 nW of the tunable 10-μm radiation are generated. This power level is enough to investigate the linear absorption spectroscopy of SF6. Doppler-limited spectra over 2 GHz are recorded, showing the wide continuous tunability of the spectrometer.
|Number of pages||7|
|Journal||IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control|
|Publication status||Published - Jan 1 2000|
ASJC Scopus subject areas
- Acoustics and Ultrasonics
- Electrical and Electronic Engineering