Interaction-Driven Surface Chern Insulator in Nodal Line Semimetals
Interaction-Driven Surface Chern Insulator in Nodal Line Semimetals
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DOI：
10.1103/physrevlett.122.016803
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发表时间：
2019-01-09
影响因子：
8.6
通讯作者：
Lado, J. L.
中科院分区：
文献类型：
--
作者：
Chen, Wei;Lado, J. L.
节线半金属的特点是非平凡的体带交叉，产生几乎平坦的鼓面状表面态（DSS），这提供了一个有吸引力的游乐场，相互作用可以诱导破缺态和潜在的紧急阶段。在这里，我们表明，电子相互作用驱动的Stoner铁磁不稳定性的DSS，而大部分仍然是不稳定的，这与自旋轨道耦合驱动的表面状态到一个2D化学绝缘体。我们发现，每一块的DSS进行半整数拓扑电荷，其中包含两块DSS的系统产生一个净陈数C =-1。我们表明，这种现象对于手征对称性破缺是鲁棒的，手征对称性破缺会给DSS带来有限的色散。我们的研究结果表明，节线半金属是一个很有前途的平台，实现表面陈绝缘体和无耗散电子输运，利用增强相互作用的DSS的效果。
Nodal line semimetals are characterized by nontrivial bulk-band crossings, giving rise to almost flat drumheadlike surface states (DSS), which provide an attractive playground where interaction can induce symmetry-broken states and potential emergent phases. Here, we show that electronic interaction drives a Stoner ferromagnetic instability in the DSS while the bulk remains nonmagnetic, which together with spin-orbit coupling drive the surface states into a 2D Chem insulator. We show that each piece of DSS carries a half-integer topological charge, which for systems containing two pieces of DSS yield a net Chern number C = - 1. We show that this phenomenology is robust against chiral-symmetry breaking, which gives a finite dispersion to the DSS. Our results show that nodal line semimetals are a promising platform to implement surface Chern insulators and dissipationless electron transport by exploiting enhanced interaction effects of the DSS.