Anomalous Electron Dynamics Induced through the Valley Magnetic Domain: A Pathway to Valleytronic Current Processing

Abstract

An interplay between an applied strain and the Berry curvature reconstruction in the uniaxially strained monolayer MoS2 is explored that leads to the unbalanced Berry curvatures centered at K and -K points and, eventually, the valley magnetization under an external electric field. This is shown to explain a recent experimental observation of the valley magnetoelectric effect and develop a novel concept of the valley magnetic domain (VMD), i.e., a real-space homogeneous distribution of the valley magnetization. A realization of VMD guarantees a sufficient number of stable valley-polarized carriers, one of the most essential prerequisites of the valleytronics. Furthermore, we discover the anomalous electron dynamics through the VMD activation and achieve a manipulation of the anomalous transverse current perpendicular to the electric field, directly accessible to the signal processing [for instance, the current modulation under the VMD (i.e., the VMD wall) moving and the terahertz current rectification under the VMD switching]. This suggests a concept of VMD for use in providing new physical insight into the valleytronic functionality and its manipulation as a key ingredient of potential device applications. © 2019 American Chemical Society.