High-spin to low-spin and orbital polarization transitions in multiorbital Mott systems.
High-spin to low-spin and orbital polarization transitions in multiorbital Mott systems.
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DOI：
10.1103/physrevlett.99.126405
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发表时间：
2007-04
影响因子：
8.6
通讯作者：
P. Werner;A. Millis
中科院分区：
文献类型：
--
作者：
P. Werner;A. Millis
我们在一个双轨模型中研究了晶体场分裂和洪德耦合的相互作用，该模型捕捉了e(g)壳层中有两个电子或空穴的系统的基本物理特性。我们使用单点动力学平均场理论和最近开发的杂质求解器，它能够获得强耦合和低温。轨道的填充和相边界的位置作为库仑排斥、交换耦合和晶体场分裂的函数来计算。我们发现Hund耦合可以驱动系统进入一个新的Mott绝缘相位，轨道磁化率消失。在非半填充状态下，晶体场分裂可诱发轨道选择性莫特态。
We study the interplay of crystal field splitting and Hund coupling in a two-orbital model which captures the essential physics of systems with two electrons or holes in the e(g) shell. We use single site dynamical mean field theory with a recently developed impurity solver, which is able to access strong couplings and low temperatures. The fillings of the orbitals and the location of phase boundaries are computed as a function of Coulomb repulsion, exchange coupling, and crystal field splitting. We find that the Hund coupling can drive the system into a novel Mott insulating phase with vanishing orbital susceptibility. Away from half-filling, the crystal field splitting can induce an orbital selective Mott state.