论文标题
强场引起的电子密度潮汐在高谐波中从固体中产生
Strong field induced electron density tide in high harmonic generation from solids
论文作者
论文摘要
在强的激光场中，固体中的电子密度可以显示由电子在电子潮汐（EDT）形成电子密度潮汐（EDT）的激光``拉动''引起的潮汐运动。但是，固体中的强场过程始终由单活动电子（SAE）模型来解释，而背景电子的波动先前被忽略。在这里，我们证明了强场诱导的EDT效应，并提出了一个模型，以揭示其在固体中的高谐产（HHG）中的作用。我们表明，EDT效应诱导超出SAE近似的额外极化电流。它为HHG提供了一种新的机制，并导致新的各向异性结构，并通过MGO在实验上观察到。我们的实验表明，随着激光强度的增加，EDT效应变得更加明显。我们的工作建立了由强激光场引起的固体中HHG和微观EDT之间的桥梁，这为探测超快电子动力学铺平了道路。
In strong laser fields, the electron density in solids can show up tidal motions caused by the laser ``pulling'' on the electrons, which forms an electron density tide (EDT). However, the strong field processes in solids are always explained by the single-active-electron (SAE) model and the fluctuation of background electrons is neglected previously. Here, we demonstrate the strong field induced EDT effect and propose a model for revealing its role in high harmoinc generation (HHG) from solids. We show that the EDT effect induces an additional polarization current beyond the SAE approximation. It gives a new mechanism for HHG and leads to new anisotropic structures, which are experimentally observed with MgO. Our experiment indicates that the EDT effect becomes more obvious with increasing the laser intensity. Our work establishes the bridge between the HHG and the microscopic EDT in solids induced by the strong laser field, which paves the way to probe the ultrafast electron dynamics.
