Fractional quantum Hall states of dipolar fermions in a strained optical lattice
Fractional quantum Hall states of dipolar fermions in a strained optical lattice
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应变光学晶格中偶极费米子的分数量子霍尔态
DOI：
10.1103/physreva.94.043641
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发表时间：
2016
影响因子：
2.9
通讯作者：
and M. Ueda
中科院分区：
文献类型：
--
作者：
H. Fujita;Y. O. Nakagawa;Y. Ashida;and M. Ueda
研究了具有跳跃幅度空间变化的蜂窝光学晶格中偶极费米子的强关联基态。类似于应变石墨烯，这种不均匀的跳跃幅度为两个狄拉克点附近的费米子产生与山谷相关的假磁场，导致朗道能级的形成。垂直于蜂窝平面排列的偶极矩产生了长程排斥相互作用。通过在零-朗道能级基下的精确对角化，我们证明了这种排斥相互作用稳定了各种谷极化的分数量子霍尔态，如Laughlin态和复合费米子态。因此，本系统为在静态光学晶格中模拟分数量子霍尔物理提供了一个有趣的平台。我们计算了这些不可压缩态以上的能隙，并讨论了实验实现它们所需的温度标度。
We study strongly correlated ground states of dipolar fermions in a honeycomb optical lattice with spatial variations in hopping amplitudes. Similar to strained graphene, such nonuniform hopping amplitudes produce valley-dependent pseudomagnetic fields for fermions near the two Dirac points, resulting in the formation of Landau levels. The dipole moments aligned perpendicular to the honeycomb plane yield a long-range repulsive interaction. By exact diagonalization in the zeroth-Landau-level basis, we show that this repulsive interaction stabilizes a variety of valley-polarized fractional quantum Hall states such as Laughlin and composite-fermion states. The present system thus offers an intriguing platform for emulating fractional quantum Hall physics in a static optical lattice. We calculate the energy gaps above these incompressible states and discuss the temperature scales required for their experimental realization.