迪拉克圆在双部分方形八角格子:一个理论方法
1College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
The Journal of chemical physics
|July 31, 2023
概括
研究人员探索了四角格子来创建迪拉克,发现它们可以通过跳跃的能量来调整. 这项工作为设计具有特定对称性的新迪拉克材料提供了基础.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
背景情况:
- 在对称的正方形格子中实现迪拉克圆是具有挑战性的.
- 双部分四角格子提供了一个潜在的替代结构.
研究的目的:
- 调查二部分四角格子中的迪拉克形形成.
- 探索迪拉克圆属性的可调性.
- 为设计新的迪拉克材料提供理论指导.
主要方法:
- 使用紧固结合 (TB) 模型进行理论调查.
- 密度函数理论 (DFT) 对实际系统的计算.
- 应用"分割并合"方法.
主要成果:
- 节点线半金属性质预测相同的现场能量.
- 圆的迪拉克圆预测不同的现场能量.
- 通过跳跃的能量来调整可调的物理性质 (异极性,倾斜性,合并性,出现性).
- 为迪拉克点位置和存在标准推导的分析公式.
- DFT计算证实了对t-BN,t-Si,graphyne和t-SiC等材料的预测.
结论:
- 双部分四角格子对实现迪拉克圆有很大的希望.
- 跳跃能量为迪拉克形属性提供了一个控制机制.
- 这项研究为设计四边形迪拉克材料提供了理论框架.
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