Open AccessIndirect-direct band gap transition driven by strain in semiconducting Cu2Se monolayer
Author(s) -
Renjun Du,
Liming Li,
Wei Shangguan,
Jinming Cai,
Jianhui Dai,
Lei Gao,
Cuixia Yan
Publication year - 2021
Publication title -
materials research express
Language(s) - English
Resource type - Journals
ISSN - 2053-1591
DOI - 10.1088/2053-1591/abf0b9
Subject(s) - monolayer , materials science , band gap , direct and indirect band gaps , condensed matter physics , fermi level , phonon , electronic structure , transition metal , strain (injury) , optoelectronics , nanotechnology , chemistry , physics , medicine , biochemistry , quantum mechanics , catalysis , electron
Cu 2 Se monolayer (ML) synthesized experimentally is a member of transition metal chalcogenides materials, which has attracted significant attention due to its diversity and unique properties. However, the feature of an indirect band gap of Cu 2 Se ML in the low-temperature phase limits its’ application in electronics devices. Our study results based on the first principle calculations show that indirect-direct band gap transitions can occur in Cu 2 Se ML under appropriate uniaxial or biaxial strains. The band gap of Cu 2 Se ML is controllable due to the different responses of the edge-states near the Fermi level to the strain. The phonon dispersion suggests that the semiconducting Cu 2 Se ML can maintain dynamic stability in a wide range of strains. With the tunable electronic structure, semiconducting Cu 2 Se ML would become a promising candidate for electronic devices.