自旋-轨道耦合、晶体场分裂与关联效应的相互作用：ghost旋转不变 slave-boson 方法研究
Interplay of spin-orbit coupling, crystal field splitting and correlations: a ghost rotationally invariant slave boson treatment
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中文总结 AI 辅助
本研究采用ghost旋转不变 slave-boson 方法（GRISB），结合Sr$_2$RuO$_4$紧束缚模型，探究自旋-轨道耦合、晶体场分裂与电子关联的相互作用，揭示$U$、$J$对SOC的影响及费米面随应变的 Lifshitz 相变。
中文摘要 AI 辅助
我们在新近提出的ghost旋转不变 slave-boson 方法（GRISB）框架下，研究$t_{2g}$ Hubbard-Kanamori模型中自旋-轨道耦合（SOC）、晶体场分裂与电子关联效应的相互作用。具体而言，我们采用从密度泛函理论和线性化准粒子自洽GW（LQSGW）计算提取参数的Sr$_2$RuO$_4$紧束缚模型，研究当ghost数目增加时不同物理量的行为，以检验GRISB向动力学平均场理论（DMFT）及实验结果的收敛性；并利用GRISB在低温宽参数范围内研究模型的能力，重点分析由SOC驱动的静态与动力学可观测量，及其随哈伯德$U$和洪德耦合$J$的变化。结果显示，GRISB对多数可观测量收敛迅速，$U$增强SOC而$J$抑制SOC；我们还研究了不同方法下的费米面形状，以及该材料随应变发生的 Lifshitz 相变。
英文摘要
We investigate the interplay of spin-orbit coupling, crystal field splittings, and electronic correlations in the $t_{2g}$ Hubbard-Kanamori model within the recently formulated ghost rotationally invariant slave-boson method (GRISB). In particular, we study a tight binding model of Sr$_2$RuO$_4$ with parameters extracted from density functional theory and linearized quasiparticle self-consistent GW (LQSGW) calculations; we study the behavior of different physical quantities as the number of ghosts increases to examine the convergence of GRISB to dynamical mean field theory (DMFT) and experimental results; and we leverage the ability of GRISB to investigate the model over a wide range of parameters at low temperature. In particular, we examine both static and dynamical observables driven by the spin orbit coupling (SOC) and study how they vary as a function of the Hubbard $U$ and Hund's coupling $J$. GRISB converges quickly for most of these observables, and the calculations reveal the following: $U$ enhances the spin-orbit coupling while $J$ suppresses it. We also study the shape of the Fermi surface within different methodologies, and examine the Lifshitz transition which takes place as a function of strain in this material.
