Topological metals induced by the Zeeman effect
Song Sun, Zhida Song, Hongming Weng, Xi Dai
Abstract
In this paper, we propose a new topological classification for Zeeman split Fermi surfaces of centrosymmetric metals under external magnetic field, where the Zeeman effect is described by the momentum-dependent $g$-factor tensor. With three important experimental effects, modification of spin-zero effect, Zeeman-effect-induced Fermi surface Chern number, and the in-plane anomalous Hall effect, we reveal that the additional Zeeman-induced Berry curvature plays a crucial role in the electron dynamics for metals under magnetic field, which has been overlooked for decades. By first-principles calculations, we study all these effects on two typical material, ${\mathrm{ZrTe}}_{5}$ and ${\mathrm{TaAs}}_{2}$ and the results are in good agreement with the existing experiments.