Feasibility of using singly resonant parametric oscillators for intracavity infrared spectroscopy

A singly resonant parametric oscillator was used for intracavity infrared spectroscopy with conversion to the visible range. A prototype of such an oscillator utilizing an LiJO₃ crystal demonstrated that intracavity selective losses amounting to 10^–2 per trip gave rise to a dip of about 20% depth in the emission spectrum, in agreement with theoretical predictions. The sensitivity of the method could be increased by increasing the duration of the pump pulses reaching the oscillator.