Magnetoconductivity of a metal with closed Fermi surface reconstructed by a biaxial density wave

TL;DR

This paper models the quantum dynamics of a 2D metal with a reconstructed Fermi surface under strong magnetic fields, revealing giant magnetoconductivity oscillations and Hall coefficient sign changes, potentially explaining experimental observations in high-Tc cuprates.

Contribution

It introduces a new theoretical framework for understanding magnetoconductivity in metals with reconstructed Fermi surfaces due to biaxial density waves.

Findings

Giant oscillations in longitudinal magnetoconductivity.

Hall coefficient changes sign over magnetic field range.

Proposed mechanism aligns with experimental data in cuprates.

Abstract

We investigate quantum dynamics and kinetics of a 2D conductor with closed Fermi surface reconstructed by a biaxial density wave, in which electrons move along a two-dimensional periodic net of semiclassical trajectories coupled by the magnetic breakdown tunnelling under a strong magnetic field. We derive a quasi-particle dispersion law and magnetoconductivity tensor. The quasi-particle spectrum is found to be the alternating series of two-dimensional magnetic energy bands with gaps between them. The longitudinal magnetoconductivity shows giant oscillations with change of magnetic field, while the Hall coefficient changes sign and is absent in a wide range of the magnetic fields in between. Preliminary estimations show that the suggested magnetoconductivity mechanism may be the origin of such behaviour of the Hall coefficient vs. magnetic field, as observed in experiments in materials with analogous topology of the Fermi surface, such as the high-Tc superconducting cuprates.