Longitudinal interlayer magnetoresistance in quasi-2D metals

TL;DR

This paper calculates the longitudinal interlayer magnetoresistance in strongly anisotropic layered metals, revealing a linear to square-root field dependence transition influenced by impurity scattering, which aids in probing electronic structures of quasi-2D materials.

Contribution

It provides a theoretical analysis of interlayer magnetoresistance behavior in quasi-2D metals, highlighting impurity effects and a method to estimate interlayer transfer integral from experimental data.

Findings

Linear magnetoresistance in certain field regimes

Square-root dependence at higher fields

Robustness of magnetoresistance to temperature and disorder

Abstract

The longitudinal interlayer magnetoresistance $R_{zz}(B_{z})$ is calculated in strongly anisotropic layered metals, when the interlayer band width $4t_{z}$ is less than the Landau level separation $\hbar \omega_{c}$. The impurity scattering has much stronger effect in this regime than in 3D metals and leads to a linear longitudinal interlayer magnetoresistance $R_{zz}\propto B_{z}$ in the interval $\hbar \omega_{c}>4t_{z}>>\sqrt{\Gamma_{0}\hbar \omega_{c}}$ changing to a square-root dependence $R_{zz}\propto B_{z}^{1/2}$ at higher field or smaller $t_{z}$. The crossover field allows to estimate the interlayer transfer integral as $t_{z}\sim \sqrt{\Gamma_{0}\hbar \omega_{c}}$. Longitudinal interlayer magnetoresistance, being robust to the increase of temperature or long-range disorder, is easy for measurements and provides a useful tool to investigate the electronic structure of quasi-two-dimensional compounds.