Charge density waves enhance the electronic noise of manganites

TL;DR

This study investigates the noise and transport properties of Pr_{0.7}Ca_{0.3}MnO_{3} thin films, revealing evidence of charge density wave behavior and proposing noise analysis as a key tool for understanding correlated electronic states.

Contribution

It demonstrates that noise spectra analysis can identify charge density wave transport mechanisms in manganites, challenging standard charge ordering models.

Findings

Broadband 1/f noise consistent with charge density wave sliding

Resistance dependence on electric field supports collective transport

Noise analysis offers a new approach to study charge-modulated states

Abstract

The transport and noise properties of Pr_{0.7}Ca_{0.3}MnO_{3} epitaxial thin films in the temperature range from room temperature to 160 K are reported. It is shown that both the broadband 1/f noise properties and the dependence of resistance on electric field are consistent with the idea of a collective electrical transport, as in the classical model of sliding charge density waves. On the other hand, the observations cannot be reconciled with standard models of charge ordering and charge melting. Methodologically, it is proposed to consider noise-spectra analysis as a unique tool for the identification of the transport mechanism in such highly correlated systems. On the basis of the results, the electrical transport is envisaged as one of the most effective ways to understand the nature of the insulating, charge-modulated ground states in manganites.