Tunable electronic structure in twisted WTe2/WSe2 heterojunction bilayer
Zi-Si Chen,
Wen-Ti Guo,
Jiefeng Ye,
Kehua Zhong,
Jian-Min Zhang,
Zhigao Huang
Affiliations
Zi-Si Chen
Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials, College of Physics and Energy, Fujian Normal University, Fuzhou 350117, China and Fujian Provincial Collaborative Innovation Center for Advanced High-Field Superconducting Materials and Engineering, Fuzhou 350117, China
Wen-Ti Guo
Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials, College of Physics and Energy, Fujian Normal University, Fuzhou 350117, China and Fujian Provincial Collaborative Innovation Center for Advanced High-Field Superconducting Materials and Engineering, Fuzhou 350117, China
Jiefeng Ye
Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials, College of Physics and Energy, Fujian Normal University, Fuzhou 350117, China and Fujian Provincial Collaborative Innovation Center for Advanced High-Field Superconducting Materials and Engineering, Fuzhou 350117, China
Kehua Zhong
Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials, College of Physics and Energy, Fujian Normal University, Fuzhou 350117, China and Fujian Provincial Collaborative Innovation Center for Advanced High-Field Superconducting Materials and Engineering, Fuzhou 350117, China
Jian-Min Zhang
Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials, College of Physics and Energy, Fujian Normal University, Fuzhou 350117, China and Fujian Provincial Collaborative Innovation Center for Advanced High-Field Superconducting Materials and Engineering, Fuzhou 350117, China
Zhigao Huang
Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials, College of Physics and Energy, Fujian Normal University, Fuzhou 350117, China and Fujian Provincial Collaborative Innovation Center for Advanced High-Field Superconducting Materials and Engineering, Fuzhou 350117, China
Electronic structures of non-twisted and twisted WTe2/WSe2 heterojunction bilayers were investigated using first-principles calculations. Our results show that, for the twisted WTe2/WSe2 heterojunction bilayer, the bandgaps are all direct bandgaps, and the bandgap (K–K) increases significantly when the twist angle is from 0° to 10°. However, when the twist angle is from 11° to 14.2°, the bandgaps are all indirect bandgaps and the bandgap (G–K) significantly reduces. The band structure of the twisted WTe2/WSe2 heterojunction bilayer differs significantly from that of the non-twisted. Twisted WTe2/WSe2 heterojunction bilayers can be seen as a direct bandgap to an indirect bandgap conversion when turned to a certain angle. Interestingly, the bandgap of the WTe2/WSe2 heterojunction bilayer is very sensitive to the change in the twist angle. For example, when the twist angle is 10.5°, a maximum bandgap will appear. However, the minimum bandgap is 0.041 eV at 14.2°. Our findings have important guidance for device tuning of two-dimensional heterojunction materials.
