Depolarization loss analysis of electro-optic crystal KDP heated by repetition frequency laser

Temperature and thermal stress distributions in the KDP, heated by repetition frequency laser, are given by means of finite element methods. Depolarized loss, which is induced by temperature dependence of the refractive index, electro-optic coefficient, and by thermal-stress, is calculated. The simulated results indicate: variation of electro-optic coefficient as well as stress birefringence is the main factor, which induces depolarized loss of the switch. When the average power of the incident laser is 40 W, after 420 s irradiation, the highest temperature in KDP crystal is 38.43 ℃. The largest depolarized loss induced by variation of electro-optic coefficient and stress birefringence is correspondingly 2.38%, 4.04%. Depolarized loss, induced by stress birefringence, is measured. The mea