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arXiv · 1212.5326

Overlaying optical lattices for simulation of complex frustrated antiferromagnets

Zhi-Xin Chen·Han Ma·Mo-Han Chen·Xiang-Fa Zhou·Lixin He·Guang-Can Guo·Xingxiang Zhou·Yan Chen·Zheng-Wei Zhou
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Abstract

We present design techniques of special optical lattices that allow quantum simulation of spin frustration in two-dimensional systems. By carefully overlaying optical lattices with different periods and orientations, we are able to adjust the ratio between the nearest-neighbor and next-nearest-neighbor interaction strengths in a square spin lattice and realize frustration effects. We show that only laser beams of a single frequency is required, and the parameter space reachable in our design is broad enough to study the important phases in the $J_1$-$J_2$ frustrated Heisenberg model and checkerboard antiferromagnet model. By using the polarization spectroscopy for detection, distinct quantum phases and quantum phase transition points can be characterized straightforwardly. Our design thus offers a suitable setup for simulation of frustrated spin systems.

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Zhi-Xin Chen, Han Ma, Mo-Han Chen, Xiang-Fa Zhou, Lixin He, Guang-Can Guo, Xingxiang Zhou, Yan Chen, Zheng-Wei Zhou. 2012-12-21. Overlaying optical lattices for simulation of complex frustrated antiferromagnets. https://doi.org/10.1103/physreva.85.013632

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