Adiabatic Chiral Magnetic Effect in Weyl semimetal wires

Artem Ivashko; Vadim Cheianov

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arXiv · 1712.05613

Adiabatic Chiral Magnetic Effect in Weyl semimetal wires

Artem Ivashko·Vadim Cheianov

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Abstract

The Chiral Magnetic Effect (CME) is a phenomenon by which an electric current develops in the direction of a magnetic field applied to a material. Recent theoretical research suggests that the CME can be observed in thermal equilibrium provided that the magnetic field oscillates with finite frequency $\omega$. Moreover, under certain conditions the amplitude of the electric current does not vanish in the adiabatic $\omega \to 0$ limit, which we call here the adiabatic CME. In this work, we consider an adiabatic CME in a bounded sample. We demonstrate that the presence of the boundary significantly changes the nature of the effect. Using linear response theory, we derive a simple formula (conjectured earlier in arXiv:1512.02144) that enables us to describe the CME in a bounded setting based on the knowledge of the energy levels alone. We use this formula to investigate a particularly interesting example of the CME completely defined by the boundary effects.

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Artem Ivashko, Vadim Cheianov. 2017-12-15. Adiabatic Chiral Magnetic Effect in Weyl semimetal wires. https://arxiv.org/abs/1712.05613

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