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arXiv · 1912.02749

Anomalous Transition Magnetic Moments in two-dimensional Dirac Materials

Sanghita Sengupta·Madalina I. Furis·Oleg P. Sushkov·Valeri N. Kotov
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Abstract

We show that the magnetic response of atomically thin materials with Dirac spectrum and spin-orbit interactions can exhibit strong dependence on electron-electron interactions. While graphene itself has a very small spin-orbit coupling, various two-dimensional (2D) compounds "beyond graphene" are good candidates to exhibit the strong interplay between spin-orbit and Coulomb interactions. Materials in this class include dichalcogenides (such as MoS$_2$ and WSe$_2$), silicene, germanene, as well as 2D topological insulators described by the Kane-Mele model. We present a unified theory for their in-plane magnetic field response leading to "anomalous", i.e. electron interaction dependent transition moments. Our predictions can be potentially used to construct unique magnetic probes with high sensitivity to electron correlations.

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Sanghita Sengupta, Madalina I. Furis, Oleg P. Sushkov, Valeri N. Kotov. 2019-12-05. Anomalous Transition Magnetic Moments in two-dimensional Dirac Materials. https://doi.org/10.1103/physrevb.102.024432

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