$p$ -块方网层导数的统一低能有效哈密顿量和能带拓扑
Unified low-energy effective Hamiltonian and the band topology of $p$-block square-net layer derivatives
摘要：
近年来，具有$p$ -块单元的方网（链状）亚结构的四元$P4/nmm$（正交$Pnma$）空间群的低维材料得到了广泛的研究。利用第一性原理计算和双位$\otimes$双轨道紧束缚模型，构造了不同填充因子下这类材料的统一低能有效哈密顿量和$\mathbb{Z}_{2}$拓扑相图.在化学势附近，我们发现离子在2c（4c）位的交错排列产生了虚跳跃，其形式与方网（链状）离子之间的第二近邻跳跃相同。我们发现，这种杂交和低对称性的链状结构保护量子自旋霍尔绝缘体相。最后，考虑了原子自旋轨道耦合之上的二阶自旋轨道耦合，解释了最近量子振荡实验中出现的非零Berry相位信号的来源.
英文摘要：
In recent years, low-dimensional materials with tetragonal $P4/nmm$ (orthorhombic $Pnma$) space group having square-net (chain-like) substructure of $p$-block elements have been studied extensively. By using a first-principles calculation and a two-sites $\otimes$ two-orbitals tight-binding model, we construct the unified low-energy effective Hamiltonian and the $\mathbb{Z}_{2}$ topological phase diagram for such materials with different filling factors. Near the chemical potential, we show that the staggered arrangement of ions at 2c (4c) site yields the virtual hopping that have the same form with the second nearest-neighbor hopping between the square-net (chain-like) ions. We show that this hybridization and low-symmetry of the chain-like structure protects the quantum spin Hall insulator phase. Finally, the second order spin-orbit coupling on top of the atomic spin-orbit coupling is considered to clarify the origin of the non-zero Berry phase signals reported in recent quantum oscillation experiments.
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。
