Conductivity of Layered Crystals

TL;DR

This paper explains how resistive anisotropy in layered crystals depends on phase coherence lengths, revealing that incoherent interlayer transport results in temperature-dependent anisotropy and coexistence of metallic and non-metallic conductivities.

Contribution

It introduces a model linking resistive anisotropy to phase coherence lengths, especially for incoherent interlayer transport in layered cuprates.

Findings

Resistive anisotropy is determined by phase coherence length ratio.

Incoherent interlayer transport leads to temperature-independent out-of-plane coherence.

Layered cuprates exhibit metallic in-plane and non-metallic out-of-plane conductivities.

Abstract

We show that the resistive anisotropy of an anisotropic medium is determined by the ratio of the phase coherence lengths. In layered crystals in which the interlayer transport is incoherent, the out-of-plane phase coherence length is fixed and temperature independent. This leads to a temperature dependent resistive anisotropy and to the coexistence of metallic in-plane and non-metallic out-of-plane conductivities. Our approach provides a description of the c-axis conductivity in the highly nonclassical regime, characteristic of layered cuprates.