论文标题
量子动力学方程的非线性光学响应
Nonlinear optical response from quantum kinetic equation
论文作者
论文摘要
由在拓扑半学中观察到的非线性霍尔效应的动机，我们通过量子动力学方程研究了光电流。我们回收了Sipe等人发现的移位电流和注入电流，以及由Inti Sodemann和Liang Fu提出的浆果曲率偶极子（BCD）引起的非线性霍尔电流。特别是，我们进一步提出，除浆果曲率和BCD外，3形式张量还可以诱导光电流。这项工作将补充现有的光电流机制。与偏移载体诱导的移位电流相反，浆果曲率的梯度/卷曲诱导的所有光电以及高等级张量都需要循环极化的光和拓扑上的非平凡带结构，即。非变化浆果曲率。
Motivated by the nonlinear Hall effect observed in topological semimetals, we studied the photocurrent by the quantum kinetic equation. We recovered the shift current and injection current discovered by Sipe et al., and the nonlinear Hall current induced by Berry curvature dipole (BCD) proposed by Inti Sodemann and Liang Fu. Especially, we further proposed that 3-form tensor can also induce photocurrent, in addition to the Berry curvature and BCD. This work will supplement the existing mechanisms for photocurrent. In contrast to the shift current induced by shift vector, all photocurrents induced by gradient/curl of Berry curvature, and high rank tensor require circularly polarized light and topologically non-trivial band structure, viz. non-vanishing Berry curvature.
