Magnetoresistance and magnetic breakdown in the quasi-two-dimensional conductors (BEDT-TTF)$_2$MHg(SCN)$_4$[M=K,Rb,Tl]

TL;DR

This paper investigates how magnetic fields affect the resistance of certain quasi-two-dimensional conductors in the density-wave phase, using a model involving magnetic breakdown and Fermi surface reconstruction, supported by high-field measurements.

Contribution

It introduces a simple theoretical model explaining resistance behavior in these conductors, validated by high-field experimental data and implications for their phase diagram.

Findings

Magnetic breakdown explains resistance changes in the conductors.

The energy gap of the density-wave phase is estimated from the data.

Results align with independent scattering time measurements.

Abstract

The magnetic field dependence of the resistance of (BEDT-TTF)$_2$MHg(SCN)$_4$[M=K,Rb,Tl] in the density-wave phase is explained in terms of a simple model involving magnetic breakdown and a reconstructed Fermi surface. The theory is compared to measurements in pulsed magnetic fields up to 51 T. The value implied for the scattering time is consistent with independent determinations. The energy gap associated with the density-wave phase is deduced from the magnetic breakdown field. Our results have important implications for the phase diagram.