论文标题
固有的费米表面对散装光伏效应的贡献
Intrinsic Fermi Surface Contribution to the Bulk Photovoltaic Effect
论文作者
论文摘要
我们研究了在超清洁极限的空间均匀光场中以二次阶顺序对非线性直流光电流的费米表面贡献。除了偏移和注入电流外，我们还发现，在金属系统上的极化光还产生了对来自费米表面上光诱导的电子跃迁的大量光伏效应的内在贡献。在{速度}仪表中，该贡献既起源于密度矩阵的偏对对角线和对角线部分，分别描述了一个相干波函数进化和激发群体的载体动力学。我们得出了一个固有的费米表面贡献的公式，用于用圆形光照明的时间反转手性韦伊尔半分化。在低频率下，此响应与驱动场的频率成正比，其符号由Weyl节点的拓扑电荷确定，并且其幅度与最近发现的量化圆形光钙化效应相当。我们的工作为非线性直流光电流的所有贡献提供了一个完整的推导，并根据TRS存在和不存在光线的极化对它们进行了分类。
We study the Fermi surface contribution to the nonlinear DC photocurrent at quadratic order in a spatially uniform optical field in the ultra-clean limit. In addition to shift and injection current, we find that polarized light incident on a metallic system generates an intrinsic contribution to the bulk photovoltaic effect deriving from photoinduced electronic transitions on the Fermi surface. In {velocity} gauge, this contribution originates in both the coherent band off-diagonal and diagonal parts of the density matrix, describing respectively, the coherent wave function evolution and the carrier dynamics of an excited population. We derive a formula for the intrinsic Fermi surface contribution for a time-reversal invariant chiral Weyl semimetal illuminated with circularly-polarized light. At low frequency, this response is proportional to the frequency of the driving field, with its sign determined by the topological charge of the Weyl nodes and with its magnitude being comparable to the recently discovered quantized circular photogalvanic effect. Our work presents a complete derivation for all contributions to nonlinear DC photocurrent and classify them according to the polarization of light in the presence and absence of TRS.
