Theoretical Description of Ferroelectric and Pyroelectric Hysteresis in the Disordered Ferroelectric-Semiconductor Films

TL;DR

This paper presents a modified Landau-Khalatnikov model that accounts for inhomogeneous switching in disordered ferroelectric-semiconductors, accurately describing their pyroelectric hysteresis behavior.

Contribution

The authors develop a theoretical model incorporating polar lattice and charged defects to better predict hysteresis in disordered ferroelectric-semiconductors.

Findings

Model reproduces realistic hysteresis loop shapes.

Describes both Pb(Zr,Ti)O3 and (Sr,Ba)Nb2O6 films.

Accounts for inhomogeneous switching phenomena.

Abstract

We have modified Landau-Khalatnikov approach and shown that both the polar lattice and the screened charged defects determine the response of disordered ferroelectric-semiconductors. This system exhibits the spatially inhomogeneous switching under the external field while Landau-Khalatnikov model describes homogeneous switching with the sharp pyroelectric coefficient peak near the thermodynamic coercive field value. Our model gives more realistic pyroelectric hysteresis loop shape without any peaks near the coercive field and describes both qualitatively and quantitatively typical Pb(Zr,Ti)O_3 and (Sr,Ba)Nb_2O_6 films pyroelectric hysteresis loops.