激光二极管抽运被动调Q周期极化铌酸锂腔内倍频激光特性的研究  

Passively Q-Switched Periodically Poled LiNbO_3 Intracavity Frequency-Doubling Laser Pumped by Diode-Laser

作　　者：张少军[1] 王青圃[2] 徐现刚[1] 董春明[1] 张行愚[2] 李平[2] 张伟[2] 刘兆军[2] 李昀初[2] 

机构地区：[1]山东大学晶体材料研究所晶体材料国家重点实验室,济南250100 [2]山东大学光学系,济南250100

出　　处：《光学学报》2004年第4期481-484,共4页Acta Optica Sinica

基　　金：国家自然科学基金 (6 99780 0 9);教育部高校骨干教师基金资助;山东省自然科学基金资助课题

摘　　要：提出了将饱和吸收Cr4+ ∶YAG晶体被动调Q开关同时作为布儒斯特片在三镜V型折叠谐振腔中起像散补偿作用的腔内倍频设计方案。在连续激光二极管端面抽运情况下 ,给出了V型谐振腔结构光束束腰半径和位置、像散补偿Cr4+ ∶YAG晶体的厚度和谐振腔折光角度的设计方法以及计算公式。采用周期极化铌酸锂晶体作为倍频元件 ,由于谐振腔内的基波和谐波具有相同的偏振方向 ,避免了腔内双折射引起的绿光噪声问题 ,得到了输出稳定的序列脉冲。在连续抽运功率为 5 0 0mW时 ,得到了平均功率 4 2 .A folded 3-mirror laser resonator in which a Cr 4+∶YAG crystal is employed as a saturable absorber for passively Q-switching and a Brewster plate to compensate astigmatism was designed. The resonator has small radius of laser waists, so it is very suitable to the laser diode pumped intercavity frequency-doubling lasers with quasi-phase-matched frequency-doubler. The expressions to calculate the radius and the place of laser waist, curvature of the mirrors used in the resonator, the thickness of a Brewster plate, and folding angle of the resonator were presented. The performance of continous-wave laser diode pumped passively Q-switched PPLN intercavity frequency-doubling laser with the folded 3-mirror laser resonator was investigated. As the result that both fundamental and second harmonic waves have the same polarization, no green-noise problem exists. The pulse series of laser output are stable. The laser has the average output power 42.7 mW under the CW input power 500 mW.

关 键 词：激光技术 被动调Q 激光二极管抽运 腔内倍频 周期极化 铌酸锂晶体 像散补偿 

分 类 号：TN248.1[电子电信—物理电子学]