Author Affiliations
Abstract
Research Center of Laser Fusion, CAEP, P.O. Box 919-988, Mianyang 621900, China
Thermal stress can induce birefringence in a laser medium, which can cause depolarization of the laser. The depolarization effect will be very severe in a high-average-power laser. Because the depolarization will make the frequency doubling efficiency decline, it should be compensated. In this paper, the thermal characteristics of two kinds of materials are analyzed in respect of temperature, thermal deformation and thermal stress. The depolarization result from thermal stress was simulated. Depolarization on non-uniform pumping was also simulated, and the compensation method is discussed.
depolarization depolarization compensation thermal birefringence High Power Laser Science and Engineering
2015, 3(1): 010000e9
Author Affiliations
Abstract
Research Center of Laser Fusion (RCLF), CAEP, P.O. Box 919-988, Mianyang, Sichuan 621900, China
The high repetition rate 10 J/10 ns Yb:YAG laser system and its key techniques are reported. The amplifiers in this system have a multi-pass V-shape structure and the heat in the amplifiers is removed by means of laminar water flow. In the main amplifier, the laser is four-pass, and an approximately 8.5 J/1 Hz/10 ns output is achieved in the primary test. The far-field of the output beam is approximately 10 times the diffraction limit. Because of the higher levels of amplified spontaneous emission (ASE) in the main amplifier, the output energy is lower than expected. At the end we discuss some measures that can improve the properties of the laser system.
Yb:YAG V-shape amplifier water-cooled 10 J laser system High Power Laser Science and Engineering
2014, 2(3): 03000e27
中国工程物理研究院 激光聚变研究中心, 绵阳 621900
为了实现高功率Yb∶YAG激光器的高效冷却,对大口径片状Yb∶YAG激光器的水冷结构进行了设计,采用有限元方法对该结构的传热效果进行了数值模拟,得到了该结构的表面对流传热系数、换热面的温度分布等参量。结果表明,该设计可以得到均匀的传热系数分布和温度分布,传热系数达到1.8×104W/(m2·K),介质表面温差在1K以内,换热效果良好。
激光技术 对流换热 高功率激光器 传热系数 温度分布 laser technique heat convection high power laser coefficient of heat transfer temperature distribution