Materials for Lasers: Frequency Conversion, Q-Switching, and Active Materials

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 309 11.1.1 Motivation for Laser Damage Studies in Materials for Lasers e development of more and more powerful and compact lasers raises the issue of laser damage of optical components in the laser sources. Active materials (like Nd:YAG crystals), frequency conversion crystals (like KDP crystals), and Q-switching components (such as RTP Pockels cells) are the main optical elements in a laser system. Hence, these materials are particularly concerned by laser damage phenomena due to intense laser irradiation. Moreover, these materials oen have a lower laser damage threshold than glasses. In addition, nonlinear eects proper to crystals (such as second harmonic generation) also can reduce the laser damage threshold of these components. us, laser-active materials and nonlinear crystals are oen a limitation for the generation or use of intense laser beams.