Dynamical scaling of $YBa_2Cu_3O_{7-\delta}$ thin film conductivity in zero field

TL;DR

This study investigates the dynamic fluctuation effects in YBa2Cu3O7−δ thin films near the critical temperature using microwave conductivity and DC measurements, revealing a dynamical scaling exponent consistent with model E-dynamics.

Contribution

It provides the first detailed analysis of frequency-dependent microwave conductivity in these films, establishing a precise dynamical scaling exponent and confirming theoretical models.

Findings

Dynamical scaling exponent z=1.55±0.15

Consistent with model E-dynamics

Effective analysis of fluctuation effects in thin films

Abstract

We study dynamic fluctuation effects of $YBa_2Cu_3O_{7-\delta}$ thin films in zero field around $T_c$ by doing frequency-dependent microwave conductivity measurements at different powers. The length scales probed in the experiments are varied systematically allowing us to analyze data which are not affected by the finite thickness of the films, and to observe single-parameter scaling. DC current-voltage characteristics have also been measured to independently probe fluctuations in the same samples. The combination of DC and microwave measurements allows us to precisely determine critical parameters. Our results give a dynamical scaling exponent $z=1.55\pm0.15$, which is consistent with model E-dynamics.