论文标题
与金属条带近端的Weyl Semimetals的隧道理论
Tunnelling theory of Weyl semimetals in proximity to a metallic band
论文作者
论文摘要
我们研究了隧穿对裂纹的Weyl半分（WSM）的隧道对带结构和费米电弧的影响。当耦合到非磁性抛物面带时，WSM的手性弧状态降低了能量和形式，以及先前延伸的状态，在Weyl节点附近的界面光谱中明显的自旋依赖性不对称性。我们通过晶格模型研究这些效果，该效果我们在有限样本上通过数值求解，并通过在无限样本上使用ANSATZ进行分析。我们的Ansatz与数值模拟非常吻合，因为它准确地描述了手性态的行为，从其能量不对称到界面处的旋转。我们发现隧道有效地增加了费米电弧长度，从而使裸露的韦尔节点的界面状态存在。这些额外的状态可能沿界面携带电流，可以在电导中检测到它们的贡献。在整个界面上，自旋不依赖的电导再现了电子隧穿实验的结果，以揭示WSM的状态密度。除电导率外，在量子振荡实验中可以看到WSM和金属带之间的隧穿的影响，我们简要评论了。
We study the effects of tunnelling on the band structure and Fermi arc of a time-reversal broken Weyl semimetal (WSM). When coupled to a non-magnetic parabolic band, the WSM's chiral arc state lowers in energy and forms, together with a previously extended state, a noticeable spin-dependent asymmetry in the interface spectrum in the vicinity of the Weyl nodes. We study these effects with a lattice model which we solve numerically on a finite sample and analytically through using an ansatz on an infinite sample. Our ansatz agrees very well with the numerical simulation as it accurately describes the behaviour of the chiral state, from its energy asymmetry to the spin canting at the interface. We find that the tunnelling effectively increases the Fermi arc length, allowing for the presence of interface states beyond the bare Weyl nodes. These additional states may carry current along the interface and their contribution can be detected in the conductance. Across the interface, the spin-independent conductance reproduces the results of an electron tunnelling experiment to reveal the WSM's density of states. Besides conductivity, the effect of tunnelling between the WSM and the metallic band can be seen in quantum oscillations experiments which we briefly comment about.
