论文标题
具有较高对称性的广义基塔伊夫模型的负符号无符号公式
Negative sign free formulations of generalized Kitaev models with higher symmetries
论文作者
论文摘要
我们为具有较高对称性的广义基塔伊夫模型提供了辅助场量子量子量算法的无符号公式。我们的表述基于自由度自由度和相位固定方法的Abrikosov fermion表示[phys。 Rev. B 104，L081106（2021）]。将费米风味或轨道的数量从一个提高到$ n $，可以将固有的$ z_2 $全局对称性推广到z $ _2 $ _2 $ _2 $ \ times $ su（$ n $）$ _ o $。使用这种通用方法，我们研究了Z $ _2 $$ \ times $ su（2）$ _ o $ kitaev-heisenberg模型，反映了各向同性海森伯格交换和基塔夫型债券方向交流之间的竞争。我们表明，对称性增强为避免挫败感提供了一条途径，并且原始Z $ _2 $对称模型中的自旋液相中不存在此模型。然而，地面相图非常丰富，并且具有更高的全球和局部连续对称性以及限定的量子临界点。
We provide a negative-sign-free formulation of the auxiliary field quantum Monte Carlo algorithm for generalized Kitaev models with higher symmetries. Our formulation is based on the Abrikosov fermion representation of the spin-1/2 degree of freedom and the phase pinning approach [Phys. Rev. B 104, L081106 (2021)]. Enhancing the number of fermion flavors or orbitals from one to $N$ allows one to generalize the inherent $Z_2$ global symmetry to Z$_2$$\times$SU($N$)$_o$. Using this general approach, we study the Z$_2$$\times$SU(2)$_o$ Kitaev-Heisenberg model reflecting the competition between the isotropic Heisenberg exchange and Kitaev-type bond-directional exchange interactions. We show that the symmetry enhancement provides a path to escape frustration and that the spin liquid phases in the original Z$_2$ symmetric model are not present in this model. Nevertheless, the ground-state phase diagram is extremely rich and has points with higher global and local continuous symmetries as well as de-confined quantum critical points.
