论文标题
旋转的光学晶格：可调式平坦带和larkin-ovchinnikov超级流体
Spin-twisted Optical Lattices: Tunable Flat Bands and Larkin-Ovchinnikov Superfluids
论文作者
论文摘要
在扭曲的双层石墨烯和过渡金属二分法中，Moiré超级晶格已经成为工程新型带结构和二维量子材料的量子阶段的强大工具。在这里，我们研究了Moiré物理学从扭曲原子（伪）旋转状态（而不是双层）的两个独立的六边形光学晶格中出现的，它们与扭曲的双层石墨烯具有明显不同的物理学。我们采用动量空间的紧密结合计算，其中包括所有范围的真实空间隧道，并表明所有扭曲角度$θ\ sillsim 6^{\ circ} $可能会变成支持缝制平坦乐队的魔术。由于平坦带附近的状态密度大大提高，因此可以通过弱吸引人的相互作用将系统驱动到超流体。令人惊讶的是，超流相阶段对应于带有有限动量配对的larkin-ovchinnikov状态，这是由于平面带和独特的单层旋转式晶格中的平面带和旋转间相互作用之间的相互作用所致。我们的工作可能为探索新型量子阶段和冷原子系统中的互联网铺平道路。
Moiré superlattices in twisted bilayer graphene and transition-metal dichalcogenides have emerged as a powerful tool for engineering novel band structures and quantum phases of two-dimensional quantum materials. Here we investigate Moiré physics emerging from twisting two independent hexagonal optical lattices of atomic (pseudo-)spin states (instead of bilayers), which exhibits remarkably different physics from twisted bilayer graphene. We employ a momentum-space tight-binding calculation that includes all range real-space tunnelings, and show that all twist angles $θ\lesssim 6^{\circ }$ can become magic that support gapped flat bands. Due to greatly enhanced density of states near the flat bands, the system can be driven to superfluid by weak attractive interaction. Strikingly, the superfluid phase corresponds to a Larkin-Ovchinnikov state with finite momentum pairing, resulting from the interplay between flat bands and inter-spin interactions in the unique single-layer spin-twisted lattice. Our work may pave the way for exploring novel quantum phases and twistronics in cold atomic systems.
