Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA and Department of Physics, Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China and Institute for Advanced Study, Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
Phys Rev Lett. 2013 Sep 20;111(12):120402. doi: 10.1103/PhysRevLett.111.120402.
Chern insulators are band insulators which exhibit a gap in the bulk and gapless excitations in the edge. Detection of Chern insulators is a serious challenge in cold atoms since the Hall transport measurements are technically unrealistic for neutral atoms. By establishing a natural correspondence between the time-reversal invariant topological insulator and the quantum anomalous Hall system, we show for a class of Chern insulators that the topology can be determined by only measuring Bloch eigenstates at highly symmetric points of the Brillouin zone. Furthermore, we introduce two experimental schemes, including the spin-resolved Bloch oscillation, to carry out the measurement. These schemes are highly feasible under realistic experimental conditions. Our results may provide a powerful tool to detect topological phases in cold atoms.
Chern 绝缘体是带隙绝缘体,在体相中存在能隙,而在边缘中存在无能隙激发。在冷原子中,Chern 绝缘体的检测是一个严峻的挑战,因为对于中性原子,霍尔输运测量在技术上是不现实的。通过在时间反演不变拓扑绝缘体和量子反常霍尔系统之间建立自然对应关系,我们表明对于一类 Chern 绝缘体,拓扑性质可以仅通过测量布里渊区高度对称点的 Bloch 本征态来确定。此外,我们引入了两种实验方案,包括自旋分辨的 Bloch 振荡,以进行测量。在现实的实验条件下,这些方案具有高度可行性。我们的结果可能为在冷原子中检测拓扑相提供一个强大的工具。