Pressure dependence of the magnetoresistance oscillations spectrum of beta''-(BEDT-TTF)4(NH4)[Fe(C2O4)3].DMF

TL;DR

This study investigates how pressure affects the magnetoresistance oscillations in a quasi-two-dimensional organic metal, revealing stable Fermi surface topology but complex pressure-dependent scattering behaviors.

Contribution

It provides the first detailed analysis of pressure effects on the magnetoresistance oscillations and Fermi surface topology of beta''-(BEDT-TTF)4(NH4)[Fe(C2O4)3].DMF.

Findings

Fermi surface topology remains qualitatively unchanged under pressure.

All oscillation frequencies show consistent pressure dependence.

Non-monotonous variations in scattering rates are observed with pressure.

Abstract

The pressure dependence of the interlayer magnetoresistance of the quasi-two dimensional organic metal beta''-(BEDT-TTF)4(NH4)[Fe(C2O4)3].DMF has been investigated up to 1 GPa in pulsed magnetic fields up to 55 T. The Shubnikov-de Haas oscillations spectra can be interpreted on the basis of three compensated orbits in all the pressure range studied, suggesting that the Fermi surface topology remains qualitatively the same as the applied pressure varies. In addition, all the observed frequencies, normalized to their value at ambient pressure, exhibit the same sizeable pressure dependence. Despite this behavior, which is at variance with that of numerous charge transfer salts based on the BEDT-TTF molecule, non-monotonous pressure-induced variations of parameters such as the scattering rate linked to the various detected orbits are observed.