电四极矩对高次谐波产生的贡献  

Contribution of electric quadrupole moment to high order harmonic generation in high-intensity laser field

作　　者：陈加幸 乔豪学[1] CHEN Jia-Xing;QIAO Hao-Xue(School of Physics and Technology,Wuhan University,Wuhan 430072,China)

机构地区：[1]武汉大学物理科学与技术学院

出　　处：《原子与分子物理学报》2019年第5期794-798,共5页Journal of Atomic and Molecular Physics

基　　金：国家自然科学基金(11674253)

摘　　要：通过数值求解强场近似下单电子原子的含时薛定谔方程,研究了在强线偏振激光场下,氢原子电四极矩对高次谐波产生的贡献.研究结果表明,在强激光场的作用下,在偶极矩的影响下氢原子能够产生奇次谐波,当激光场强度增加到一定值时,氢原子在电四极矩的作用下产生了偶次谐波.根据谐波功率谱和时频分析图并结合半经典“三步模型”分析了偶次高次谐波产生机制,并对产生的物理现象做出了合理的解释.The time-dependent Schrodinger equation of the single electron atom in three-dimensional spherical coordinates is numerically solved,and the contribution of the electric quadrupole moment to the generation of high-order harmonics is studied under the interaction of the intensity linearly polarized laser field and the hydrogen atom.We find that under the influence of the dipole moment the hydrogen atom emits odd harmonics in the intensity laser field while under the action of the electric quadrupole moment the hydrogen atom emits even harmonics in the intensity laser field.By analyzing the power spectrum and the picture of the time-frequency combined with semi-classical“three-step model”,the mechanism and reasons of the even high harmonics generation are explained reasonably.

关 键 词：高次谐波 偶次谐波 电四极矩 强激光场 

分 类 号：O562.4[理学—原子与分子物理]