Pressure effects on Dirac fermions in {\alpha}-(BEDT-TTF)2I3

TL;DR

This paper studies how applying pressure affects the Dirac fermions in a layered organic compound, revealing changes in the electronic structure and magnetoresistance through theoretical modeling and experimental data.

Contribution

It provides a detailed analysis of pressure-induced modifications in Dirac fermions in { extalpha}-(BEDT-TTF)2I3 using tight-binding models and experimental observations.

Findings

Dirac fermion spectrum can vanish under pressure

Pressure induces a gap opening in the electronic structure

Inter-layer magnetoresistance varies with pressure

Abstract

We investigate the pressure effect on the layered Dirac fermion system, which is realized in quasi-two-dimensional organic compound {\alpha}-(BEDT-TTF)2I3. The trajectory of the contact points is investigated using the tight-binding model with the transfer integrals determined by X-ray diffraction experiments. Vanishing of the Dirac fermion spectrum, opening of the gap, and pressure dependence of inter-layer magnetoresistance are discussed.