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arXiv · 1405.3975

Chiral Topological Orders in an Optical Raman Lattice

Xiong-Jun Liu·Zheng-Xin Liu·K. T. Law·W. Vincent Liu·T. K. Ng
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Abstract

We find an optical Raman lattice without spin-orbit coupling showing chiral topological orders for cold atoms. Two incident plane-wave lasers are applied to generate simultaneously a double-well square lattice and periodic Raman couplings, the latter of which drive the nearest-neighbor hopping and create a staggered flux pattern across the lattice. Such a minimal setup is can yield the quantum anomalous Hall effect in the single particle regime, while in the interacting regime it achieves the $J_1$-$J_2$-$K$ model with all parameters controllable, which supports a chiral spin liquid phase. We further show that heating in the present optical Raman lattice is reduced by more than one order of magnitude compared with the conventional laser-assisted tunneling schemes. This suggests that the predicted topological states be well reachable with the current experimental capability.

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Xiong-Jun Liu, Zheng-Xin Liu, K. T. Law, W. Vincent Liu, T. K. Ng. 2014-09-14. Chiral Topological Orders in an Optical Raman Lattice. https://doi.org/10.1088/1367-2630%2F18%2F3%2F035004

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