双色三束激光场优化产生超短阿秒脉冲.docVIP

双色三束激光场优化产生超短阿秒脉冲 摘要新型超强超短脉冲激光的出现与发展为人类提供了前所未有的全新实验手段与极端的物理条件。目前,高次谐波是产生阿秒脉冲的主要来源。众所周知,物质是由分子和原子组成的，但它们不是静止的，这是微观物质的一个非常重要的基本属性。阿秒脉冲最直接的应用就是原子内部电子过程的观测。本论文围绕提高高次谐波的产生效率、通过平台区超连续谱的产生进一步优化控制单个阿秒这两个方面展开了详细讨论。首先介绍了阿秒激光的相关原理，其中包括高次谐波产生的三步模型、量子轨道的选取、相位匹配原理、时频分析方法和量子波包LZH-DICP并行程序。其次，本文从理论上说明了可以通过调节双色三束激光场的相位延迟，可在高次谐波平台区产生波段连续可调的极紫外线超连续谱，并进一步研究了高次谐波产生的相位匹配控制。最后，通过调节双色三束激光场相对相位选取了高次谐波的长短轨道。11643 关键词高次谐波 三步模型 阿秒脉冲 双色三束激光场 相位匹配 量子轨道 时频分析 LZH-DICP 毕业设计说明书（论文）外文摘要 TitleOptimization of two-colour three-beam laser field to generate ultrashot attosecond pulse Abstract The emergence and development of strong intense and ultrashort pulse laser to provide new unprecedented experimental methods and the extreme physical conditions. At present, the high-order harmonic generation (HHG) is the main source of attosecond pulse. It is well known that the matter is composed of molecules and atoms, but they are not static, which is a basic property in the microscopic view. The most direct application of the attosecond pulse is to observe the atomic internal electronic process. The main focus of this thesis is to improve the energy conversion efficiency of HHG, as well as the optimal control of single attosecond pulse through the supercontinuum generation in the high-order harmonic plateau region. First, this work introduces the classical lsquo;three-steprsquo; model, the selection of quantum paths, the phase-matching control of HHG, wavelet time-frequency analyses, as well as the parallel quantum wavepacket computer code LZH-DICP. Second, we numerically demonstrate that an XUV supercontinuum in the high-order harmonic plateau region can be obtained using a two-colour three-beam laser field with a second harmonic pulse added to the fundamental-wave pulse. The generated supercontinuum can be controlled by changing the pulse durations. Then we investigate the phase-matching control of HHG. Finally, we successfully select the long and short quantum paths in HHG process by adjusting the relat