论文标题
固有的非线性欧姆电流
An intrinsic nonlinear Ohmic current
论文作者
论文摘要
众所周知,磁金属中的固有电流通常出现在垂直于外部场的方向上,以实现线性和非线性响应。与三种已知的非线性电流不同,即DRUDE贡献,浆果曲率偶极诱导的电流和浆果连接极化引起的电流,在这里我们报告了具有破坏时间反转对称性的内在非线性电流。这种新型的来自非平凡浆果连接性极化性的内在非线性电流可能会沿纵向或横向出现,并且两者都是散发性的欧姆电流。我们推出66个可以容纳这种非线性电流的磁点组对称性,并提出了可能的候选材料。该理论还用于观察我们在一维迪拉克系统中提出的非线性电流作为示例。
It is known that intrinsic currents in magnetic metals often appear in the direction perpendicular to the external field for linear and nonlinear responses. Distinct from three kinds of known nonlinear currents, namely, the Drude contribution, the Berry curvature dipole induced current and the Berry connection polarization induced current, here we report a intrinsic nonlinear current with breaking time-reversal symmetry. This new kind of intrinsic nonlinear current from the nontrivial Berry connection polarizability may emerge in the longitudinal or transverse direction, and both are dissipative Ohmic currents. We unveil 66 magnetic point group symmetries that can accommodate such nonlinear current, and possible candidate materials are proposed. This theory is also applied to observe the nonlinear current we proposed in one- and two-dimensional Dirac systems as examples.