Fundamental studies on the laser diode pumped solid-state laser driver

研究了激光二极管泵浦固体激光驱动器用于核聚变反应堆的技术和经济可行性，选择了激光波长为1mum的掺钕固体激光材料。采用概念设计技术，设计了一个电抗器驱动器的原型模型，该驱动器具有在0.35 μ m波长下每脉冲输出能量为4MJ，总效率为12%，重复频率为12Hz的规格。通过LD泵浦Nd: YAG激光系统的小型实验，证明了Lowdermilk和Murray理论可以作为高能高效激光驱动的指导原则。提出了一种高效的LD阵列表面泵浦Nd: YAG磁盘放大器，其光-光转换效率为12%。用一种新设计的偏振计成功地测量了圆盘放大器的二维热应力双折射。得到了65%的能量提取效率，该效率很好地拟合了考虑热双折射损失的Frantz-Nodvik方程。为了测量Yb激光器的荧光寿命，实现了宽可调谐（750-1040nm）全固态KTP参数转换器，该转换器具有低泵浦能量阈值（532nm, 8ns， 50Hz输入为0.4mJ）和高转换效率（27%）。

Technical and economical feasibility of a laser diode (LD) pumped solid-state laser driver for the fusion reactor is examined, Nd-doped solid-state laser materials with lasing wavelength at 1mum are serected. Using a conceptual designing technique, a prototype-model driver is designed, which has the specifications for a reactor driver such as an output energy of 4MJ per pulse at the wavelegth of 0.35mum, overall efficiency of 12% and a repetition rate of 12Hz.According to a small scale experiment of an LD pumped Nd : YAG laser system, it is shown that the Lowdermilk and Murray theory can be used as a guide line when a high-energy high-efficiency laser driver.An efficient LD array surface pumped Nd : YAG disk amplifier with an optical-optical conversion efficiency of 12% is demonstrated. Tow -dimensional thermal stress-induced birefingence in the disk amplifier is successfully measured using a newly designed polarimeter. An energy extraction efficiency of 65% is obtained which is well fitted to the Frantz-Nodvik equations taking into account of the thermal birefringent loss.To measure the fluorescence lifetime of Yb lasant, a widely tunable (750-1040nm) all-solid-state KTP parametric converter featuring low pump energy threshold (0.4mJ for the 532nm, 8ns, 50Hz input) and high conversion efficiency (27%) is realized.