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arXiv · 1804.09420

Topological Insulator State due to Finite Spin-Orbit Interaction in an Organic Dirac Fermion System

Toshihito Osada
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Abstract

Recently, Valenti et al. pointed out the significance of the spin-orbit interaction (SOI) in organic materials, and explained the anomalous insulating behavior of a Dirac semimetal alpha-(BEDT-TTF)2I3 at low temperatures in terms of the small SOI gap. We propose a lattice model with plausible SOI coupling, and indicate that the gapped state is a topological insulator. This model is an organic analogue of the Kane-Mele model for graphene.

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Toshihito Osada. 2018-04-25. Topological Insulator State due to Finite Spin-Orbit Interaction in an Organic Dirac Fermion System. https://doi.org/10.7566/jpsj.87.075002

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