双光束Raman组束研究

Research on Raman Combination with Two Abberated Pump Beams

着重研究了双光束拉曼组束改善准分子激光光束质量。通过理论计算得出，在畸变泵浦光作用下可以获得近衍射极限Ｓｔｏｋｅｓ光的放大。并在稳态和瞬态激光脉冲的条件下，讨论了Ｒａｍａｎ工作介质的选择。在此基础上进行了氯化氙准分子激光在氢气中的双光束Ｒａｍａｎ组束实验研究，近衍射极限Ｓｔｏｋｅｓ光在获得功率放大的同时，其远场分布保持不变。激光聚焦亮度提高约３０００倍。最后讨论了放大自发辐射的抑制。

We have investigated Raman beam combination to improve the beam quality of a XeCl excimer laser.It was verified theoretically that the near diffraction-limited Stokes light could be obtained with abberated pump beams.The selection of Raman gas media was then discussed on steady and transient pump pulse conditions.Experimentally,we studied the Raman combining in H2 with two pump beams.The near diffraction-limited Stokes light was amplified intensely with unchanged far field distribution,resulting in a brightness increase of 3000 times.Finally we discussed the amplified spontaneous emission in a Ramanamplifier.