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Constructing the Dirac Electronic Behavior Database of Under-Stress Transition Metal Dichalcogenides for Broad
Xiao Wu1,2, Mingzi Sun3,4, Haitao Yu1,2
1CAS Center for Excellence in Nanoscience, Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing, 100083, China.
Abstract:
Discovering and utilizing the unique optoelectronic properties of transition metal dichalcogenides (TMDCs) is of great significance for developing next-generation electronic devices. In particular, research on Dirac state modulations of TMDCs under external strains is lacking. To fill this research gap, it has established a comprehensive database of 90 types of TMDCs and their response behaviors under external strains have been systematically investigated regarding the presence of Dirac cones and electronic structure evolutions. Among all the conditions, 27.3% of the TMDCs are Dirac materials with three distinct types of Dirac cones, which are mainly attributed to the electron localizations induced by external strains. TMDCs based on tellurides with 1H phase favor the formation of Dirac cones under stresses, leading to metallic-like properties and ultra-fast charge transportation. Correlations among Dirac cones, energy, electronic properties, and lattice structures have been revealed, offering critical references for modulating the properties of well-known TMDCs. More importantly, it has confirmed that the phase transition points are not sufficient for the appearance of Dirac cones. This work provides critical guidance to facilitate the development of TMDCs-based superconducting and optoelectronic devices for broad applications.
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