论文标题
全息厅的异常电导率
Anomalous Hall conductivity of the holographic $\mathbb{Z}_2$ Dirac semimetals
论文作者
论文摘要
详细阐述了用晶体对称性保护的两个狄拉克节点的全息模型中的异常自旋霍尔电导率。除手性异常外，此类系统还具有与$ \ Mathbb {z} _2 $拓扑费有关的另一种异常。该系统的全息模型包含具有两个$ u（1）$量规场以及Chern-Simons量规术语的合适组合的物质动作。 我们还允许将两个量规场{\ i i}耦合，该动力学混合通过耦合$α$进行了参数。探针限制中的全息方法使我们能够获得霍尔电导率。这项工作的目的是描述$ \ mathbb {z} _2 $ dirac半学之间的相变，拓扑上琐碎的阶段和非平凡阶段。有趣的是，异常的霍尔电导率起着该相变的顺序参数的作用。全息在拓扑非平凡的阶段中发现了霍尔电导率的预成分，取决于耦合$α$和Chern -Simons耦合。
The anomalous spin Hall conductivity in the holographic model of Dirac semimetals with two Dirac nodes protected by the crystal symmetry has been elaborated. Such system besides the chiral anomaly possesses another anomaly which is related to the $\mathbb{Z}_2$ topological charge of the system. The holographic model of the system contains matter action with two $U(1)$-gauge fields as well as the appropriate combination of the Chern-Simons gauge terms. We also allow for the coupling of two gauge fields {\it via} the kinetic mixing parametrised by the coupling $α$. The holographic approach in the probe limit enables us to obtain Hall conductivity. The aim of this work is to describe the phase transitions in the $\mathbb{Z}_2$ Dirac semimetals between the topologically trivial and non-trivial phases. Interestingly the anomalous Hall conductivity plays a role of the order parameter of this phase transition. The holographically found prefactor of the Hall conductivity in the topologically non-trivial phase, depends on the coupling $α$ and the Chern - Simons couplings.
