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arXiv · 1402.6502

Topological metallic states in spin-orbit coupled bilayer systems

Hui Pan·Xin Li·Zhenhua Qiao·Cheng-Cheng Liu·Yugui Yao·Shengyuan A. Yang
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Abstract

We investigate the influence of different spin-orbit couplings on topological phase transitions in the bilayer Kane-Mele model. We find that the competition between intrinsic spin-orbit coupling and Rashba spin-orbit coupling can lead to two dimensional topological metallic states with nontrivial topology. Such phases, although having a metallic bulk, still possess edge states with well-defined topological invariants. Specifically, we show that with preserved time reversal symmetry, the system can exhibit a $\mathbb{Z}_2$-metallic phase with spin helical edge states and a nontrivial $\mathbb{Z}_2$ invariant. When time reversal symmetry is broken, a Chern metallic phase could appear with chiral edge states and a nontrivial Chern invariant.

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Hui Pan, Xin Li, Zhenhua Qiao, Cheng-Cheng Liu, Yugui Yao, Shengyuan A. Yang. 2014-02-26. Topological metallic states in spin-orbit coupled bilayer systems. https://arxiv.org/abs/1402.6502

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