二维中狄拉克锥各向异性的统一描述
A Unified Description of Dirac-Cone Anisotropies in Two Dimensions
- Universidade Federal de Lavras（拉夫拉斯联邦大学）
- Universidade do Estado do Pará（帕拉州立大学）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
本文提出狄拉克方程的协变修正模型，构建统一框架表征二维狄拉克系统的各向异性效应，并应用于应变石墨烯实现有效参数的定量提取，建立微观电子结构与材料无关描述的联系。
AI中文摘要：
二维材料中的各向异性会引发多种效应，显著改变其物理性质。本文提出了狄拉克方程的一种协变修正，将各向异性纳入狄拉克点附近的有效低能描述中。该模型通过类比粒子物理标准模型的洛伦兹破缺扩展构建，形成了一个(2+1)维框架，可通过其自由参数描述位移、倾斜和畸变的狄拉克锥等物理效应。该模型因此提供了一个通用且统一的框架，可系统表征狄拉克谱的不同各向异性诱导修正及其组合。我们进一步将该模型应用于应变石墨烯，结果表明可从第一性原理电子能带结构中定量提取其有效参数，同时保留直接的几何解释。这些结果建立了微观电子结构与材料无关的各向异性二维狄拉克系统有效描述之间的联系。
英文摘要：
Anisotropies in two-dimensional materials are responsible for a variety of effects that significantly modify their physical properties. In this paper, we present a covariant modification of the Dirac equation that incorporates anisotropies into the effective low-energy description around the Dirac point. The model is constructed by analogy with a Lorentz-violating extension of the Standard Model of elementary particles and yields a (2+1)-dimensional framework describing physical effects such as shifted, tilted, and distorted Dirac cones through its free parameters. The proposed model thus provides a general and unified framework in which distinct anisotropy-induced modifications of the Dirac spectrum and their combinations can be systematically characterized. We further apply the model to strained graphene and show that its effective parameters can be quantitatively extracted from first-principles electronic band structures while retaining a direct geometrical interpretation. These results establish a connection between the microscopic electronic structure and a material-independent effective description of anisotropic two-dimensional Dirac systems.
