Evidence for Correlated Dynamics near the Berezinskii-Kosterlitz-Thouless-like Transition in Highly Underdoped La$_{2-x}$Sr$_{x}$CuO$_{4}$

TL;DR

This study investigates slow, correlated electronic dynamics near the BKT-like transition in highly underdoped La$_{2-x}$Sr$_{x}$CuO$_{4}$, revealing ergodicity breaking and the influence of disorder on these phenomena.

Contribution

It provides experimental evidence of correlated dynamics and ergodicity breaking near a BKT-like transition in underdoped cuprates, highlighting disorder's suppressive effect.

Findings

Slow, correlated dynamics observed near transition

Ergodicity breaking identified in resistance noise

Disorder suppresses correlated behavior

Abstract

A low-frequency resistance noise study in highly underdoped thick films of La$_{2-x}$Sr$_{x}$CuO$_{4}$ ($x=0.07$ and 0.08) reveals slow, correlated dynamics and breaking of ergodicity near the superconducting transition of the Berezinskii-Kosterlitz-Thouless type. The observed correlated behavior is strongly suppressed by disorder.