Possible Verification of Tilted Anisotropic Dirac Cone in \alpha-(BEDT-TTF)_2 I_3 Using Interlayer Magnetoresistance

TL;DR

This paper proposes a method to verify the presence of a tilted and anisotropic Dirac cone in a layered organic compound using interlayer magnetoresistance measurements, providing a theoretical framework for parameter determination.

Contribution

It introduces a theoretical approach to identify and analyze tilted anisotropic Dirac cones via interlayer magnetoresistance in -(BEDT-TTF)_2 I_3, including formulas for parameter extraction.

Findings

Resistivity peaks align with the tilt direction when Fermi velocity anisotropy is small.

Derived analytical formulas for Landau level wave functions in tilted anisotropic Dirac systems.

Procedure outlined for experimental determination of tilt and anisotropy parameters.

Abstract

It is proposed that the presence of a tilted and anisotropic Dirac cone can be verified using the interlayer magnetoresistance in the layered Dirac fermion system, which is realized in quasi-two-dimensional organic compound \alpha-(BEDT-TTF)_2 I_3. Theoretical formula is derived using the analytic Landau level wave functions and assuming local tunneling of electrons. It is shown that the resistivity takes the maximum in the direction of the tilt if anisotropy of the Fermi velocity of the Dirac cone is small. The procedure is described to determine the parameters of the tilt and anisotropy.