Doping stability and charge-density-wave transition of strained 1T-TiSe₂

¹ Institute of Applied Physics and Computational Mathematics - P. O. Box 8009, Beijing 100088, China
² Beijing University of Posts and Telecommunications - Beijing 100876, China
³ Department of Chemistry, School of Science, Beijing Technology and Business University - Beijing 100048, China
⁴ Beijing University of Chemical Technology - Beijing 100029, China

^(a) yang_yu@iapcm.ac.cn
^(b) zhang_ping@iapcm.ac.cn

Received: 22 August 2017
Accepted: 5 December 2017

Abstract

Through a series of first-principles calculations, we reveal the doping stabilities of strained TiSe₂ in both normal and charge density wave (CDW) states. Two critical carrier concentrations are revealed for both electron and hole dopings. The first one corresponds to the situation when CDW transition is totally eliminated after charge doping, while the second one corresponds to the situation when TiSe₂ becomes structurally unstable due to charge doping. We systematically investigate and quantitatively reveal the modulations on these two critical doping concentrations by biaxial strains. Our study serves as an important supplement to understanding phase transitions of TiSe₂, especially where charge doping or external strains are applied.