激光二极管端面泵浦Yb∶YAG薄片激光器的热效应

通过激光二极管端面泵浦Yb∶YAG薄片工作特点分析,建立了符合实际情况的热模型.热模型考虑了介质薄片具有端面绝热、周边恒温冷却、后端面镀膜达到充分利用泵浦光能量等特点.分析并建构了Poisson方程新的求解方法,得出了Yb∶YAG薄片内部温度场以及泵浦端面热形变场的一般解析表达式.理论研究结果表明:若激光二极管泵浦功率为20 W、耦合到薄片泵浦面的泵浦光高斯半径为250 μm时,长度3 mm、半径1.5 mm的5.0at.%Yd:YAG薄片泵浦端面的最高温升为44.5℃,最大热形变量为0.83 μm.

Thermal Effect of Yb: YAG Slice Laser by Diode Laser End-pumped

By the analysis of working characteristic of Yb∶YAG slice with diode laser end-pumped,a thermal model that matched practical situation was introduced.In the thermal model, some characteristics of the Yb∶YAG slice were considered,such as thermal insulation of end-faces,a constant cooling temperature around the side-face and the high reflective film on the rear surface of the slice to better absorb the pumped-power.A novel solution of the Possion equation was analyzed and established.A general solutions of temperature field and thermal distortion field of Yb∶YAG slice were obtained.The theoretical result shows that when the pumped-power of diode laser is 20 W and the Gaussian radius coupled on the pumped-face of the slice is 0.25 μm,the maximal temperature raise of Yb∶YAG slice,which the length and the radius of Yb∶YAG slice is 3 mm and 1.5 mm and the ytterbium doped concentration in Yb∶YAG slice is 5 %,is 44.5℃,and thermal distortion on pump-face is 0.83 μm.These results can offer theoretical basis in the design of stable all-solid-state Yb∶YAG laser.