DC and optical signatures of the topological reconstruction of the Fermi surface for electrons with parabolic band dispersion

TL;DR

This paper investigates how topological changes in the Fermi surface affect electronic transport and optical properties in free electron systems across two and three dimensions, revealing signatures of reconstruction.

Contribution

It provides a detailed analysis of intra-band and inter-band transport signatures associated with Fermi surface topological reconstruction in electron systems.

Findings

Optical conductivity shows a component parallel to the reconstruction wave vector.

Transport quantities exhibit dimensionality-specific features.

Signatures of Fermi surface reconstruction are identified in transport functions.

Abstract

We study the main intra-band and inter-band transport properties at zero temperature of free electron-like system undergoing a topological reconstruction of the Fermi surface for the two-dimensional and three-dimensional case. The calculated intra-band properties include the single-particle density of states, the total and the effective concentrations of electrons and the thermopower. As for the inter-band case, the real part of the conductivity has been calculated within the vanishing inter-band relaxation approximation as a function of the incident photon energy. Within this approach, it is shown that the optical conductivity has a nonvanishing component parallel to the reconstruction wave vector and the shape which depends on the value of the Fermi energy. Each dimensionality has its particular features in the transport quantities presented in the paper, which are discussed and compared with those in the free electron scenario. Finally, we identify the signature of the topological reconstruction of the Fermi surface in the intra-band and inter-band transport functions.