晶体环境下高次谐波谱的截止频率分析  

Analysis on the cutoff frequency of high order harmonic generation in the crystal

作　　者：陈高[1] 杨玉军[2] 郭福明[2] 

机构地区：[1]长春理工大学理学院物理系,长春130022 [2]吉林大学原子与分子物理研究所,长春130012

出　　处：《物理学报》2013年第8期83-88,共6页Acta Physica Sinica

基　　金：国家重点基础研究发展计划(批准号:2013CB922200);国家自然科学基金(批准号:11274141;11034003)资助的课题~~

摘　　要：通过数值求解中红外飞秒光脉冲与一维单电子多阱势相互作用的含时薛定谔方程,研究了晶体环境下的高次谐波发射光谱,发现了晶体谐波谱的截止位置公式.研究发现,不同于气体环境下的谐波谱截止频率规律,晶体谐波谱的截止频率与激光电场的峰值振幅及晶格参数成线性关系.鉴于准经典力学的三步模型对于气体谐波截止频率的解释,进一步采用准经典力学方法验证了晶体谐波截止位置规律的正确性.By numerically solving the time-dependent Schrtdinger equation with the interaction between one-dimensional multi-well potential and the mid-infrared few-cycle femtosecond pulses, we theoretically investigate the high-order harmonic generation spectra in a crystal, further find the cutoff frequency formula under the new condition. Our results clearly show that the high order harmonic generation in the crystal is fundamentally different from that in the atomic case, owing to the high density and periodic structure. The harmonics spectrum shows a cutoff position that scales linearly with the peak amplitude of electric field of the drive laser and the lattice parameters. Based on the important role of the three-step model obtained by quasi-calssical mechanics method in gas harmonic generation, in this paper, this method is also well used to verify the cutoff position law in crystal harmonic generation.

关 键 词：中红外飞秒光脉冲 晶体 高次谐波 截止频率 

分 类 号：O437[机械工程—光学工程]