Single-frequency stable neodymium glass laser with a longitudinal mode selector based on an LiF:F2– crystal

A single-frequency neodymium glass laser was constructed and the longitudinal modes were selected using an LiF crystal containing F₂^– color centers, which served also as a passive switch. A spectrally selective grating formed in such a switch during laser operation, resulting in spontaneous transformation of an initially wide spectrum into a single-frequency one. An analysis was made of the requirements which components of a single-frequency laser should satisfy and its characteristics were determined.