论文标题
固体中高谐波产生的不完美回忆
Imperfect Recollisions in High-Harmonic Generation in Solids
论文作者
论文摘要
从理论上讲，我们用线性极化激光脉冲研究了六角硼的高谐波产生。我们表明，晶体中电子孔对之间的不完善的回忆产生了电子孔对极化能，从而导致亚周期发射曲线中的双峰结构。开发了一种扩展的回忆模型（ERM），该模型允许这种不完善的回忆以及与浆果连接，浆果曲率和过渡偶极相有关的效果。 ERM阐明了平行并垂直于激光极化方向发出的谐波的独特光谱特性。不完善的回忆是一种普遍现象，是真实空间波数据包的空间定位性质的表现，它们自然出现在具有较大的浆果曲率的系统中，或者在任何由椭圆极化光线驱动的系统中。
We theoretically investigate high-harmonic generation in hexagonal boron nitride with linearly polarized laser pulses. We show that imperfect recollisions between electron-hole pairs in the crystal give rise to an electron-hole-pair polarization energy that leads to a double-peak structure in the subcycle emission profiles. An extended recollision model (ERM) is developed that allows for such imperfect recollisions, as well as effects related to Berry connections, Berry curvatures, and transition-dipole phases. The ERM illuminates the distinct spectrotemporal characteristics of harmonics emitted parallel and perpendicularly to the laser polarization direction. Imperfect recollisions are a general phenomenon and a manifestation of the spatially delocalized nature of the real-space wave packet, they arise naturally in systems with large Berry curvatures, or in any system driven by elliptically polarized light.
