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Mirror symmetry origin of Dirac cone formation in rectangular two-dimensional materials
Xuming Qin1, Yi Liu2, Gui Yang1
1School of Physics and Electrical Engineering, Anyang Normal University, Anyang 455000, P. R. China. xmqin@aynu.edu.cn.
Physical Chemistry Chemical Physics : PCCP
|March 12, 2020
Summary
A novel "mirror symmetry parity coupling" (MSPC) mechanism explains Dirac cone formation in 2D materials beyond graphene. This symmetry-based approach reveals design principles for new Dirac cone materials.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Solid-State Physics
Background:
- Dirac cones (DCs) in graphene are linked to hexagonal lattice symmetry.
- Recent findings show DCs in 2D materials with rectangular unit cells, challenging previous assumptions.
Purpose of the Study:
- To elucidate the mechanism of Dirac cone formation in 6,6,12-graphyne.
- To propose a general mechanism applicable to various 2D materials with mirror symmetry.
Main Methods:
- Utilized the tight-binding method.
- Employed density functional calculations.
- Developed and applied the
- mirror symmetry parity coupling
- (MSPC) mechanism.
Main Results:
- Proposed the MSPC mechanism to explain DC formation in 6,6,12-graphyne.
- Demonstrated that MSPC accounts for DC band structures in 2D materials with rectangular or hexagonal unit cells and mirror symmetry.
Conclusions:
- Symmetry analysis, particularly mirror symmetry, is crucial for understanding DC origins.
- The MSPC mechanism provides a design criterion for discovering novel materials with Dirac cone features.
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