Polarization effects, birefringent filtering, and single-frequency operation in lasers containing a birefringent gain crystal

The effect of having a birefringent gain crystal is studied in the context of two laser systems: an intracavity frequency-doubled microchip laser and a compact single-frequency laser utilizing a birefringent filter. A model b ased on Jones calculus is proposed to predict the polarization and waveleng th structure of the longitudinal modes and is found to be consistent with e xperimental measurements. The optimization of these systems is discussed, a nd the importance of the birefringences in the cavity and cavity length is indicated.