强场太赫兹波作用下氢气分子振动动力学研究  

Vibrational dynamics of hydrogen molecules under intense THz waves

作　　者：宁辉[1] 王凯程 王少萌[1] 宫玉彬[1] Ning Hui;Wang Kai-Cheng;Wang Shao-Meng;Gong Yu-Bin(College of Electronic Science and Engineering,University of Electronic Science and Technology of China,Chengdu 611731,China)

机构地区：[1]电子科技大学电子科学与工程学院,成都611731

出　　处：《物理学报》2021年第24期91-97,共7页Acta Physica Sinica

基　　金：国家自然科学基金(批准号61921002,61988102)资助的课题.

摘　　要：利用电磁场与分子体系的相互作用可以研究分子的物理性质及其动力学问题.不断发展的太赫兹技术提供了能够产生亚皮秒定向强电场的太赫兹源,其产生的强场太赫兹波拥有与分子局部电场环境相当的电场强度,且定向电场的亚皮秒时间尺度也能覆盖众多超快物理化学反应过程.目前太赫兹波与分子的相互作用还主要局限于共振相互作用,即电磁波通过偶极相互作用,使分子在不同的振转能级发生跃迁.本文基于密度泛函理论计算和薛定谔方程的时域有限差分求解方法,研究了强太赫兹波电场对氢分子的强场非共振作用.结果显示,在强场太赫兹波亚皮秒定向强电场的作用下,氢分子将产生诱导偶极矩,此偶极矩与外加太赫兹场作用,引起质子概率密度分布的波动及振动能级布居数的变化.本文基于非极性双原子分子氢气与强场太赫兹波的非共振作用,展示了一种独特的电磁波与分子相互作用的途径,对研究生物体非极性分子及极性较弱的分子在强太赫兹场下的动力学研究提供了方法.The physical properties and dynamics of molecules can be studied by the interaction between electromagnetic field and molecular system.The continuous development of terahertz technology provides a terahertz source capable of generating a sub-picosecond directional intense electric field.The generated intense-field terahertz wave has the same electric field intensity as the molecular local electric field environment,and on a sub-picosecond time scale of the directional electric field there can happen many ultrafast physical and chemical reactions.At present,the interaction between terahertz waves and molecules is limited mainly to the resonance interaction,that is,the molecules transition at different vibrational levels,caused through dipole interaction.In this work,based on the density functional theory calculation and the finite difference time domain solution method of Schrödinger equation,the intense non-resonance effect of intense terahertz wave electric field on hydrogen molecules is studied.The results show that under the action of intense terahertz wave sub-picosecond directional intense electric field,hydrogen molecule will produce an induced dipole moment.This dipole interacts with the external terahertz field,resulting in the fluctuation of proton probability density distribution and the change of vibration energy level population.Based on the non-resonant interaction between non-polar diatomic molecule hydrogen and intense terahertz wave,a unique way of producing the interaction between electromagnetic waves and molecules is displayed in this work,which is a method of studying the dynamics of non-polar molecules and molecules with weak polarity in intense terahertz field.

关 键 词：氢分子 太赫兹波 非共振作用 诱导偶极矩 

分 类 号：O441.4[理学—电磁学] O561[理学—物理]