论文标题
挫败感引起的扩展的玻色 - 哈伯德模型中的固体
Frustration induced incommensurate solids in the extended Bose-Hubbard model
论文作者
论文摘要
我们使用量子蒙特卡洛方法研究了与最接近的邻居和近邻居$（v，v'）$排斥相互作用的扩展的玻色 - 哈伯德模型。与强$ v'$的情况不同，地面状态可以是条纹固体或条纹超氧化物，我们专注于弱$ v'<v/2 $ and小跳，发现，在热力学极限中，分数密度的不固定固体从1/4到1/4不等。我们还表明，不连续的固体以连续的波向量从$（π，π/2）$（或$（π/2，π）$）变为$（π，π，π）$，可以通过域壁形成的机制来理解。还讨论了相关的地面相图和热相变。
We study the extended Bose-Hubbard model with nearest-neighbor and next-nearest-neighbor $(V, V')$ repulsive interactions on a square lattice by using the quantum Monte Carlo method. Unlike the case of strong $V'$ where the ground states can be striped solids or striped supersolids, we focus on weak $V' < V/2$ and small hoppings and find that, in the thermodynamic limit, incommensurate solids of fractional densities varying from 1/4 to 1/2 can be stabilized. We also show that the incommensurate solids, which are characterized by a continuous set of wave vectors changing from $(π,π/2)$ (or $(π/2,π)$) to $(π,π)$, can be understood by a mechanism of domain wall formation. The related ground-state phase diagram and thermal phase transitions are also discussed.
