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arXiv · 1612.08880

Symmetry-protected topological states for interacting fermions in alkaline-earth-like atoms

Abstract

We discuss the quantum simulation of symmetry-protected topological (SPT) states for interacting fermions in quasi-one-dimensional gases of alkaline-earth-like atoms such as $^{173}$Yb. Taking advantage of the separation of orbital and nuclear-spin degrees of freedom in these atoms, we consider Raman-assisted spin-orbit couplings in the clock states, which, together with the spin-exchange interactions in the clock-state manifolds, give rise to SPT states for interacting fermions. We numerically investigate the phase diagram of the system, and study the phase transitions between the SPT phase and the symmetry-breaking phases. The interaction-driven topological phase transition can be probed by measuring local density distribution of the topological edge modes.

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Xiaofan Zhou, Jian-Song Pan, Zheng-Xin Liu, Wei Zhang, Wei Yi, Gang Chen, Suotang Jia. 2017-10-16. Symmetry-protected topological states for interacting fermions in alkaline-earth-like atoms. https://doi.org/10.1103/physrevlett.119.185701

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