Bo Chen, Jian Liu, Lin Xue, Zhi Yang, Yong-Jia Zhang
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引用次数: 0
Abstract
Coupling valleys with different layers is a feasible way to realize valley polarization through a gate electric field, but only a few two-dimensional (2D) materials with locked valley and layer physics have been found so far. In this Letter, we show that valley-layer coupling (VLC), which is robust against spin–orbit coupling, could be achieved in 2D heterostructures built using distinct 2D monolayers with no VLC feature, as demonstrated by density functional theory calculations on Tl3Cl3/Ba2I2F2/Tl3Cl3 and Sn2Te2/K2Br2/Sn2Te2 van der Waals heterostructures. These two heterostructures exhibit valley-selective linear dichroism, which enables the optical creation of interlayer or intralayer excitons with selected valley and electric polarization. Furthermore, both the K2Br2/Sn2Te2/K2Br2 and Sn2Te2/K2ClBr/Sn2Te2 heterostructures are ferrovalley materials due to the ferroelectricity of Sn2Te2 and the built-in electric field caused by Janus K2ClBr, respectively. Our results broaden the candidate VLC materials from 2D monolayers and bilayers to 2D van der Waals heterostructures.
期刊介绍:
Applied Physics Letters (APL) features concise, up-to-date reports on significant new findings in applied physics. Emphasizing rapid dissemination of key data and new physical insights, APL offers prompt publication of new experimental and theoretical papers reporting applications of physics phenomena to all branches of science, engineering, and modern technology.
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Fast Track articles are invited original research articles that report results that are particularly novel and important or provide a significant advancement in an emerging field. Because of the urgency and scientific importance of the work, the peer review process is accelerated. If, during the review process, it becomes apparent that the paper does not meet the Fast Track criterion, it is returned to a normal track.