Charge-density-wave tuning in monolayer 1H-TaSe₂by biaxial strain and charge doping

¹ Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences Hefei 230031, China
² University of Science and Technology of China - Hefei 230026, China
³ Institutes of Physical Science and Information Technology, Anhui University - Hefei 230601, China

^(a) hywu@ahu.edu.cn
^(b) wjlu@issp.ac.cn

Received: 12 June 2019
Accepted: 19 July 2019

Abstract

Using first-principles calculations, we investigate the effects of in-plane biaxial strain and charge doping on the charge-density-wave (CDW) order of monolayer 1H-TaSe₂. Our results show that the compressive strain can enhance the CDW order, while the tensile strain suppresses the CDW order of monolayer 1H-TaSe₂. The contrary results of strain-tuned CDW orders in 1H-TaSe₂ and 1T-TiSe₂ are explained based on the different lattice distortions and responses to strain. Furthermore, we find that the electron doping can enhance the CDW order, while the hole doping suppresses the CDW order. Our results show that the strain and charge doping can effectively control the CDW order of monolayer 1H-TaSe₂, which makes monolayer 1H-TaSe₂ a candidate material for a two-dimensional CDW electronic device. Further experimental investigations are needed to confirm the present predictions.