Polarization rotation and the electrocaloric effect in barium titanate

TL;DR

This paper investigates the electrocaloric effect in BaTiO3, revealing both positive and negative effects linked to polarization rotation during phase transitions under electric field and temperature changes.

Contribution

It demonstrates the connection between polarization rotation and negative electrocaloric effect in BaTiO3's phase transitions, providing new insights into ferroelectric behavior.

Findings

Negative electrocaloric effect observed in monoclinic phases

Polarization rotation causes temperature decrease under electric field

Phase transitions influence electrocaloric response

Abstract

We study the electrocaloric effect in the classic ferroelectric BaTiO3 through a series of phase transitions driven by applied electric field and temperature. We find both negative and positive electrocaloric effects, with the negative electrocaloric effect, where temperature decreases with applied field, in monoclinic phases. Macroscopic polarization rotation is evident through the monoclinic and orthorhombic phases under applied field, and is responsible for the negative electrocaloric effect.