Magneto-conductivity and CME in Dirac semimetals from Keldysh technique in Landau levels basis

TL;DR

This paper uses the Keldysh technique to derive kinetic equations and calculate magnetoconductivity in Dirac semimetals, providing insights into the chiral magnetic effect and its experimental signatures.

Contribution

It introduces a semi-realistic model and applies the non-equilibrium diagram technique to analyze magnetoconductivity and CME in Dirac semimetals, including temperature dependence.

Findings

Calculated magnetoconductivity as a function of magnetic field and temperature.

Compared theoretical temperature dependence with experimental data.

Provided a new theoretical framework for understanding CME in Dirac semimetals.

Abstract

Negative magnetoresistance in Dirac semimetals is conventionally considered as a manifestation of chiral magnetic effect (CME), by means of a postulated Chiral Kinetic equation. In this paper we study magnetoconductivity in large Fermi energy Dirac semimetals, in one of which (ZrTe$_5$) the effect was observed for the first time. Starting with a Hamiltonian for a semi-realistic model of such a Dirac semimetal, we apply the Non-equilibrium Diagram Technique (NDT, or the Keldysh technique) to derive the kinetic equations, to investigate the electrons relaxation due to interaction with phonons and disorder, and, finally, to calculate the DC magnetoconductivity (the longitudinal to magnetic field component of conductivity) as a function of magnetic field strength and temperature. Finally, we compare the obtained temperature dependencies with available to us experimental data.