Spatial correlations and the insulating phase of the high-T(c) cuprates: insights from a configuration-interaction-based solver for dynamical mean field theory.
Spatial correlations and the insulating phase of the high-T(c) cuprates: insights from a configuration-interaction-based solver for dynamical mean field theory.
复制标题
高 T(c) 铜酸盐的空间相关性和绝缘相：来自动态平均场理论的基于配置相互作用的求解器的见解。
DOI：
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发表时间：
2013
影响因子：
8.6
通讯作者：
A. Millis
中科院分区：
文献类型：
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作者：
A. Go;A. Millis
最近提出的组态相互作用为基础的杂质求解器结合使用的单网站和四网站集群动态平均场近似调查的三带铜氧化物模型被认为是描述高转变温度的铜氧化物超导体的电子结构。使用组态相互作用求解器可以验证结果相对于浴轨道数的收敛性。包括在集群近似的空间相关性基本上移动金属-绝缘体相边界相对于单站点近似的预测，并增加约1 eV以上的单站点结果的绝缘相的预测的能隙。在四位近似中发生的顶点校正作用显著增加了差距边缘附近的光学电导率的值，导致与数据更好的一致性。计算揭示了两种不同的相关绝缘状态：“磁相关绝缘体”，其中非平凡的站点间的相关性在稳定绝缘状态中发挥着至关重要的作用，和强相关绝缘体，其中本地物理足够。比较的计算数据放置在磁相关的莫特绝缘体制度的铜酸盐。
A recently proposed configuration-interaction-based impurity solver is used in combination with the single-site and four-site cluster dynamical mean field approximations to investigate the three-band copper oxide model believed to describe the electronic structure of high transition temperature copper-oxide superconductors. Use of the configuration interaction solver enables verification of the convergence of results with respect to the number of bath orbitals. The spatial correlations included in the cluster approximation substantially shift the metal-insulator phase boundary relative to the prediction of the single-site approximation and increase the predicted energy gap of the insulating phase by about 1 eV above the single-site result. Vertex corrections occurring in the four-site approximation act to dramatically increase the value of the optical conductivity near the gap edge, resulting in better agreement with the data. The calculations reveal two distinct correlated insulating states: the "magnetically correlated insulator," in which nontrivial intersite correlations play an essential role in stabilizing the insulating state, and the strongly correlated insulator, in which local physics suffices. Comparison of the calculations to the data places the cuprates in the magnetically correlated Mott insulator regime.