论文标题
在Matsubara时间域内探索拓扑结晶绝缘子（SNS和SNSE）的依赖温度依赖的电子电子相互作用
Exploring temperature dependent electron-electron interaction of topological crystalline insulators (SnS and SnSe) within Matsubara-time domain
论文作者
论文摘要
实验和理论研究都表明，SNS和SNSE的天然岩石阶段中的非平凡拓扑行为，并将这些材料分类为拓扑结晶绝缘子。在这里，使用基于多体$ GW $的理论和密度功能理论对基接地状态和温度依赖性激发态进行了多体$ GW $的理论和密度函数理论，对SNS和SNSE的详细电子结构研究进行了。使用$ G_0W_0 $（MBJ）围绕L-Point的基本直接带盖的估计值为$ \ sim $ 0.27（$ \ sim $ 0.13）EV和$ \ sim $ 0.37（$ \ sim $ 0.17）EV，分别用于SNS和SNSE。 SN 5 $ P $和S 3 $ P $（SE 4 $ p $）SNS（SNSE）之间的杂交强度显示出很强的K依赖性。 $ \ Overline {w} $（$ω$）的行为是完全筛选的库仑相互作用的对角线矩阵元素的平均值，建议使用全$ GW $方法来探索激发态，因为这两种材料中的相关效应相对较弱。 SNS和SNSE的温度依赖性电子结构计算随温度升高提供了带镜的线性降低行为。预测这些化合物的集体激发以等离子形式的集体激发存在，其中等离子体频率的估计值分别为$ \ sim $ 9.5 eV和$ \ sim $ \ sim $ 9.3 ev，用于SNS和SNSE。由于电子 - 电子相互作用（EEI），还沿W-l- $γ$方向计算出自我能源和质量重新归化因子（$ z_ \ textbf {k}（ω）$）的假想部分。本比较研究表明，SNS和SNSE的温度依赖性EEI的行为几乎相同，EEI对于高温传输特性很重要。
Both experimental and theoretical studies show non-trivial topological behaviour in native rocksalt phase for SnS and SnSe and categorize these materials in topological crystalline insulators. Here, the detailed electronic structures studies of SnS and SnSe in the rocksalt phase are carried out using many-body $GW$ based theory and density functional theory both for ground states and temperature dependent excited states. The estimated values of fundamental direct bandgaps around L-point using $G_0W_0$ (mBJ) are $\sim$0.27 ($\sim$0.13) eV and $\sim$0.37 ($\sim$0.17) eV for SnS and SnSe, respectively. The strength of hybridization between Sn 5$p$ and S 3$p$ (Se 4$p$) orbitals for SnS (SnSe) shows strong k-dependence. The behaviour of $\overline{W}$ ($ω$), which is the averaged value of diagonal matrix elements of fully screened Coulomb interaction, suggests to use full-$GW$ method for exploring the excited states because the correlation effects within these two materials are relatively weak. The temperature dependent electronic structure calculations for SnS and SnSe provide linearly decreasing behaviour of bandgaps with rise in temperatures. The existence of collective excitation of quasiparticles in form of plasmon is predicted for these compounds, where the estimated values of plasmon frequency are $\sim$9.5 eV and $\sim$9.3 eV for SnS and SnSe, respectively. The imaginary part of self-energy and mass renormalization factor ($Z_\textbf{k}(ω)$) due to electron-electron interaction (EEI) are also calculated along W-L-$Γ$ direction for both the materials. The present comparative study reveals that the behaviour of temperature dependent EEI for SnS and SnSe are the almost same and EEI is important for high temperature transport properties.
