Electrocaloric and barocaloric effects in CsH$_2$PO$_4$ ferroelectric

TL;DR

This study models the electrocaloric and barocaloric effects in CsH$_2$PO$_4$ ferroelectric using a modified pseudospin approach, revealing temperature changes of about 1 K and -0.5 K respectively, influenced by electric field and pressure.

Contribution

It introduces a modified pseudospin model accounting for lattice strain and dipole moment dependence, to analyze caloric effects in CsH$_2$PO$_4$ ferroelectric.

Findings

Electrocaloric temperature change is about 1 K.

Barocaloric temperature change is about -0.5 K.

Electrocaloric effect can change sign under hydrostatic pressure.

Abstract

To investigate the caloric effects in the CsH$_2$PO$_4$ ferroelectric, a modified pseudospin model of this crystal is used, which takes into account the dependence of the parameters of interaction between pseudospins on lattice strains. The model also takes into account the dependence of the effective dipole moment of a pseudospin on the order parameter. In the two-particle cluster approximation, the influence of the longitudinal electric field and hydrostatic pressure on the molar entropy of the crystal was studied. The electrocaloric and barocaloric effects were studied. The calculated electrocaloric temperature change is about $1$ K; it can change its sign under the influence of hydrostatic pressure. Barocaloric temperature change is about $-0.5$ K; lattice anharmonicities were not taken into account in its calculations.