论文标题
石墨烯中质量向量子点周围的手性状态
Chiral states around a mass-inverted quantum dot in graphene
论文作者
论文摘要
通过分析紧密结合和内核多项式方法计算，研究了石墨烯中拓扑保护的手性态。通过考虑两个不同的质量结构域之间的异质结（与双层石墨烯中的域壁相似）来引入质量量子点。数值结果表明，当质量项的符号相反时，质量间隙的新兴金属通道。金属通道的特征态显示为双重变性 - 每个状态沿相反的方向传播，维持石墨烯的时间反转对称性。进一步检查了金属通道的鲁棒性，以此结论是，除非在域壁附近形成原子空位，否则要确保手性状态。这种沿拓扑缺陷循环的手性状态可能铺平了基于石墨烯的工程拓扑状态的新途径。
Topologically protected chiral states at a mass-inverted quantum dot in graphene are studied by analyzing both tight-binding and kernal polynomial method calculations. The mass-inverted quantum dot is introduced by considering a heterojunction between two different mass domains, which is similar to the domain wall in bilayer graphene. The numerical results show emergent metallic channels across the mass gap when the signs of the mass terms are opposite. The eigenstates of the metallic channels are revealed to be doubly degenerate---each state propagates along opposite directions, maintaining the time-reversal symmetry of graphene. The robustness of the metallic channels is further examined, concluding with the fact that chiral states are secured unless atomic vacancies form near the domain wall. Such chiral states circulating along the topological defects may pave a novel route to engineering topological states based on graphene.
