标题： CrSBr中相互作用诱导的电荷有序理论 显示英文标题

标题： Theory of interaction-induced charge order in CrSBr

摘要： CrSBr是一种层状范德华绝缘体，具有准一维电子结构和面内铁磁序。 最近对锂掺杂CrSBr的实验工作揭示了准一维电荷调制态。 在本研究中，我们为CrSBr开发了从头算有效模型，以研究这些态，并使用平均场理论和密度矩阵嵌入理论进行求解。 这些模型通过密度泛函理论、约束随机相位近似以及长程库仑相互作用的Rytova-Keldysh形式进行参数化。 我们的模拟表明，出现了由类似余弦的链内密度调制和链间相位偏移组成的电荷密度波态，这些偏移可最小化库仑排斥。 值得注意的是，在对应于$1/n$个电子每CrSBr单元的掺杂水平下，最稳定的图案表现出$n$个单元的周期性，这与实验观察结果和Peierls不稳定性论点一致。 此外，我们证明了链间序对库仑相互作用范围敏感。 如果相互作用被截断为短程形式，则某些局域化的条纹状态在计算上更受青睐。 这项工作为理解CrSBr及相关材料中竞争电子和磁相的相互作用提供了从头算框架。 显示英文摘要

摘要： CrSBr is a layered van der Waals insulator with a quasi one-dimensional electronic structure and in-plane ferromagnetic order. Recent experimental work on Li-doped CrSBr reveals quasi-1D charge modulated states. In this study, we develop ab initio effective models for CrSBr to investigate these states and solve them using mean-field theory and density matrix embedding theory. The models are parametrized using density functional theory, the constrained random phase approximation, and the Rytova-Keldysh form of the long-range Coulomb interaction. Our simulations indicate the emergence of a charge density wave state characterized by cosine-like intra-chain density modulations and inter-chain phase shifts that minimize the Coulomb repulsion. Notably, at a doping level corresponding to $1/n$ electron per CrSBr unit, the most stable pattern exhibits a periodicity of $n$ cells, in agreement with experimental observations and Peierls' instability arguments. Moreover, we demonstrate that the inter-chain order is sensitive to the range of Coulomb interactions. If the interaction is hard-truncated to a short-ranged form, some localized stripe-like states are computationally favored. This work provides an ab initio framework for understanding the interplay of competing electronic and magnetic phases in CrSBr and related materials.