理论研究激光强度对H2+分子高次谐波产生的影响

本文通过求解非波恩-奥本海默近似条件下的一维含时薛定谔方程来研究脉冲强度对H₂⁺分子高次谐波的影响.由于干涉相消,在啁啾激光场的条件下在谐波谱中出现了干涉最小值.我们用全量子方法计算的时频分布图分析了分子高次谐波产生中的微观机制.此外,数值计算结果显示随着脉冲强度的增加电子的有质动力势随之增加,同时干涉最小值的位置移向谐波的高阶部分.

Theoretical exploration of intensity effects on high-order harmonic generation from H2+ molecules

Non-Born-Oppenheimer time-dependent Schrödinger equation numerical simulations of the one-dimensional H2+ molecular ion in few cycle laser pulses are presented to study the effect of intensity on molecular high-order harmonic generation (HHG). The minimum in the high-order harmonic spectrum, as a consequence of the destructive interference, is appeared in the chirped laser pulse. Based on the time-frequency distributions, we analyze the underlying physics of the molecular HHG by quantum method. Our study shows that HHG is modulated by the interference, and the location of the interference minimum shifts to higher energy by a quantity of the ponderomotive energy as laser intensity increases.