Accurate spectroscopic wavelength determination of pulsed lasers

Abstract

We present a simple, easy, and straightforward spectroscopic approach for the determination of the wavelength of pulsed laser systems with an accuracy of ≤0.006 cm^-1 (180 MHz). This is better than currently realised by the best commercially available wavemeters for pulsed laser systems. As an example, the temperature dependence of the emitted wavelength of a pulsed Nd:YAG laser has been studied in detail. Our measurements indicate that the passively Q-switched monolithic nonplanar ring-oscillator Nd:YAG laser with a free spectral range of the resonator of about 5.8 GHz can be tuned without mode hops over a range of 3.8 GHz. The concept is generally applicable to any other wavelength regions of interest.