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arXiv · 2104.13547

Large Diamagnetism and Electromagnetic Duality in Two-dimensional Dirac Electron System

S. Fujiyama·H. Maebashi·N. Tajima·T. Tsumuraya·H-B. Cui·M. Ogata·R. Kato
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Abstract

A Dirac electron system in solids mimics a relativistic quantum physics that is compatible with Maxwell's equations, by which we anticipate unified electromagnetic responses. We find a large orbital diamagnetism only along the interplane direction and the nearly temperature-independent conductance of the order of e2/h for the new 2D Dirac organic conductor, a-(BETS)2I3. Distinct from conventional electrons in solids whose nonrelativistic effects bifurcate electric and magnetic responses, the observed orbital diamagnetism scales the electrical conductivity for a wide temperature range. This demonstrates that an electromagnetic duality that is valid only within the relativistic framework is revived in solids.

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S. Fujiyama, H. Maebashi, N. Tajima, T. Tsumuraya, H-B. Cui, M. Ogata, R. Kato. 2021-12-21. Large Diamagnetism and Electromagnetic Duality in Two-dimensional Dirac Electron System. https://doi.org/10.1103/physrevlett.128.027201

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