Barkhausen noise in the organic ferroelectric copolymer P(VDF:TrFE)

TL;DR

This study experimentally investigates Barkhausen noise in the organic ferroelectric copolymer P(VDF:TrFE), revealing how electric field parameters influence noise characteristics and suggesting proximity to universal critical behavior.

Contribution

First experimental analysis of Barkhausen noise in an organic ferroelectric material, exploring effects of electric field magnitude and rise time on noise statistics.

Findings

Power-law exponents increase with maximum electric field.

Rise time shifts exponents towards lower values.

Exponents tend to 1.5 under fast, strong driving conditions.

Abstract

Polarization reversal within a ferroelectric material is commonly described as a progression of smaller switching events, giving rise to crackling or Barkhausen noise. While studies on Barkhausen noise, and particularly the associated event size distribution, allow for better understanding of switching processes in ferroelectrics, they were not yet conducted experimentally on organic ferroelectric materials. In this work, Barkhausen noise in the organic ferroelectric copolymer poly(vinylidene fluoride-co-trifluoroethylene) (P(VDF:TrFE)) is experimentally investigated under different electric fields, increasing at various rates. A weak dependence of the structure of the Barkhausen noise on both the magnitude and rise time of the applied electric field is observed, which manifests as a trend in the probability density function power-law exponents. Specifically, an increase in maximum electric field leads to an increase of the power-law exponent; increasing the rise time causes a parallel shift towards lower exponents. While these findings do not allow to conclusively confirm or refute universal self-organized critical behavior of the polarization reversal avalanches in P(VDF:TrFE), the exponents were found to seemingly converge to the universal value of 1.5 for fast and strong driving, suggesting the system is close to this limit.