论文标题
向后拉曼放大的光相结合
Optical phase conjugation in backward Raman amplification
论文作者
论文摘要
使用血浆中的向后拉曼扩增（BRA）压缩激光脉冲，然后真空聚焦为小斑点，可以产生前所未有的超偏移激光强度。然而，胸罩期间的血浆密度不均匀性会导致激光相和振幅畸变，从而限制了脉冲焦点。为了解决失真问题，我们研究了将光相结合用作胸罩的种子脉冲的使用。我们表明，相结合的激光脉冲可以保留在胸罩的非线性泵止动物中的聚焦性，但在线性扩增方案中却不那么容易。这种有点反直觉的结果是因为非线性泵 - 止动物的放大距离较短，因此由于波波相互作用而引起的相变较少，而不是线性放大方案。
Compression of an intense laser pulse using backward Raman amplification (BRA) in plasma, followed by vacuum focusing to a small spot size, can produce unprecedented ultrarelativistic laser intensities. The plasma density inhomogeneity during BRA, however, causes laser phase and amplitude distortions, limiting the pulse focusability. To solve the issue of distortion, we investigate the use of optical phase conjugation as the seed pulse for BRA. We show that the phase conjugated laser pulses can retain focusability in the nonlinear pump-depletion regime of BRA, but not so easily in the linear amplification regime. This somewhat counter-intuitive result is because the nonlinear pump-depletion regime features a shorter amplification distance, and hence less phase distortion due to wave-wave interaction, than the linear amplification regime.
