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arXiv 2409.07557cond-mat.str-elcond-mat.mes-hall
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强关联下的初始量子自旋霍尔绝缘体

Incipient quantum spin Hall insulator under strong correlations

Peizhi Mai, Jinchao Zhao, Philip W. Phillips

AI总结:

通过非微扰行列式量子蒙特卡洛模拟 Kane-Mele-Hubbard 模型,本文否定平均场预测的 $z$-AFM 陈绝缘相,证明强关联下 $xy$-AFM 涨落稳定初始量子自旋霍尔绝缘体。

摘要:

为评估此前平均场研究关于相互作用 Kane-Mele 模型在很宽的子晶格势范围内承载新型 $z$-反铁磁(AFM)陈绝缘体相的主张,我们采用非微扰行列式量子蒙特卡洛模拟,分析了存在子晶格势时的 Kane-Mele-Hubbard 模型。相反,我们发现:对于中等大小的子晶格势 $λ_v$ 和较大的在位排斥,真正的低温态是量子自旋霍尔绝缘体。研究发现存在两种相互竞争的磁涨落:$z$-AFM 与 $xy$-AFM。后者在低温下占主导,从而使量子自旋霍尔态得以稳定,而不是形成 $z$-AFM 陈绝缘体。我们的工作与在扭转双层 MoTe$_2$ 和 WSe$_2$ 以及 AB 堆叠 MoTe$_2$/WSe$_2$ 中、在宽参数范围内于偶数整数填充处一致观测到的稳健量子自旋霍尔效应相符。

英文摘要:

To assess prior mean-field claims that the interacting Kane-Mele model hosts a novel $z-$antiferromagnetic (AFM) Chern insulating phase for a wide range of sub-lattice potentials, we analyze the Kane-Mele-Hubbard model in the presence of a sub-lattice potential using non-perturbative determinant quantum Monte Carlo simulations. We find instead that the true low-temperature state is a quantum spin Hall insulator for intermediate values of the sub-lattice potential $λ_v$ and large on-site repulsion. Two kinds of magnetic fluctuations are found to compete: $z$- and $xy$-AFM. The latter dominates at low temperature leading to a stabilization of the quantum spin Hall state as opposed to $z-$AFM Chern insulator. Our work is consistent with the robust quantum spin Hall effects which are consistently observed at even-integer fillings over a wide range of parameters in twisted bilayer MoTe$_2$ and WSe$_2$ as well as AB stacked MoTe$_2$/WSe$_2$.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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