Wang Huan-Yu, Zheng Zhen, Zhuang Lin, Tai Yong-Hang, Shi Jun-Sheng, Liu Wu-Ming
Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China. School of Physical Sciences, University of Chinese Academy of Sciences, Beijing100190, People's Republic of China.
J Phys Condens Matter. 2020 May 27;32(23):235701. doi: 10.1088/1361-648X/ab7871.
We investigate the topological supersolid states of dipolar Fermi gases trapped in a spin-dependent 2D optical lattice. Our results show that topological supersolid states can be achieved via the combination of topological superfluid states with the stripe order. Different from the general held belief that supersolid state in fermionic system can only survive with simultaneous coexistence of the repulsive and attractive dipolar interaction. We demonstrate that it can be maintained when the dipolar interaction is attractive in both x and y direction. By adjusting the ratio of hopping amplitude between different directions and dipolar interaction strength U, the system will undergo a phase transition among p + ip superfluid state, p -wave superfluid state, and the topological supersolid state. The supersolid state in the attractive environment is proved to be stable by the positive sign of the inverse compressibility. We also design an experimental protocol to realize the staggered next-next-nearest-neighbor hopping via the laser assisted tunneling technique, which is the key to simulate the spin-dependent potential.
我们研究了捕获在自旋相关二维光学晶格中的偶极费米气体的拓扑超固体状态。我们的结果表明,拓扑超固体状态可以通过拓扑超流体状态与条纹序的组合来实现。与一般认为费米子系统中的超固体状态只能在排斥和吸引偶极相互作用同时共存时才存在的观点不同。我们证明,当偶极相互作用在x和y方向上均为吸引时,它可以保持。通过调整不同方向之间的跳跃幅度与偶极相互作用强度U的比值,系统将在p + ip超流体状态、p波超流体状态和拓扑超固体状态之间发生相变。通过逆压缩率的正号证明了吸引环境中的超固体状态是稳定的。我们还设计了一个实验方案,通过激光辅助隧穿技术实现交错的次近邻跳跃,这是模拟自旋相关势的关键。