Valley manipulation by external fields in two-dimensional materials and their hybrid systems.

Abstract

Investigating two-dimensional (2D) valleytronic materials opens a thrilling new chapter in physics and facilitates the emergence of pioneering technologies. Nevertheless, this nascent field faces substantial challenges, primarily attributed to the inherent issue of valley energy degeneracy and the scarcity of ferrovalley materials. To break these constraints, the application of external stimuli has become pivotal for both eliciting and fine-tuning the valley properties inherent to these 2D systems. This paper thoroughly examines the recent advancements in modulating the valley properties of 2D valleytronic materials using external fields, encompassing a wide array of configurations from monolayers and bilayers to intricate heterostructures. We hope that this overview will inspire more exciting discoveries and significantly propel the evolution of valleytronics within the realm of 2D materials researchs. .