Edge States and Topological Phases in One-Dimensional Optical Superlattices
Edge States and Topological Phases in One-Dimensional Optical Superlattices
复制标题
一维光学超晶格中的边缘态和拓扑相
DOI：
10.1103/physrevlett.108.220401
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发表时间：
2012-05-29
影响因子：
8.6
通讯作者：
Chen, Shu
中科院分区：
文献类型：
--
作者：
Lang, Li-Jun;Cai, Xiaoming;Chen, Shu
我们证明一维准周期光学晶格系统可以表现出通常认为出现在二维系统中的边缘态和拓扑相。当费米能量位于能隙中时，光学超晶格上的费米系统是一个拓扑绝缘体，其特征是非零拓扑不变量。拓扑性质可以通过观察俘获费米子系统的密度分布来揭示，该系统显示出平台，其位置由双色光学晶格的波长比唯一确定。超晶格系统的蝴蝶状光谱也可以根据俘获费米子系统的有限温度密度分布来确定。这一发现为研究一维光学晶格中的拓扑相和类霍夫施塔特光谱开辟了一条替代途径。
We show that one-dimensional quasiperiodic optical lattice systems can exhibit edge states and topological phases which are generally believed to appear in two-dimensional systems. When the Fermi energy lies in gaps, the Fermi system on the optical superlattice is a topological insulator characterized by a nonzero topological invariant. The topological nature can be revealed by observing the density profile of a trapped fermion system, which displays plateaus with their positions uniquely determined by the ration of wavelengths of the bichromatic optical lattice. The butterflylike spectrum of the superlattice system can be also determined from the finite-temperature density profiles of the trapped fermion system. This finding opens an alternative avenue to study the topological phases and Hofstadter-like spectrum in one-dimensional optical lattices.