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arXiv · 1212.4839

Realizing Fractional Chern Insulators with Dipolar Spins

Norman Y. Yao·Alexey V. Gorshkov·Chris R. Laumann·Andreas M. Läuchli·Jun Ye·Mikhail D. Lukin
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Abstract

Strongly correlated quantum systems can exhibit exotic behavior controlled by topology. We predict that the ν=1/2 fractional Chern insulator arises naturally in a two-dimensional array of driven, dipolar-interacting spins. As a specific implementation, we analyze how to prepare and detect synthetic gauge potentials for the rotational excitations of ultra-cold polar molecules trapped in a deep optical lattice. While the orbital motion of the molecules is pinned, at finite densities, the rotational excitations form a fractional Chern insulator. We present a detailed experimental blueprint for KRb, and demonstrate that the energetics are consistent with near-term capabilities. Prospects for the realization of such phases in solid-state dipolar systems are discussed as are their possible applications.

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Norman Y. Yao, Alexey V. Gorshkov, Chris R. Laumann, Andreas M. Läuchli, Jun Ye, Mikhail D. Lukin. 2012-12-19. Realizing Fractional Chern Insulators with Dipolar Spins. https://doi.org/10.1103/physrevlett.110.185302

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