Abstract
A new scheme for measuring the frequency stability of a cw HF chemical laser is described. It is based on the measurement of the beat‐frequency spectrum of longitudinal modes and the mode‐pulling effect in a high‐gain medium. The mode‐pulling effect can also be used to actively stabilize the laser frequency. Experimental measurements on the mode pulling and the stability of a free‐running cw HF chemical laser agree with theory and other experimental measurements.