Electric field control of magnetocaloric effect in cylindrical MnAs/PZT magnetoelectric composite

TL;DR

This study demonstrates electric field control of the magnetocaloric effect in a MnAs/PZT composite, showing that applied voltage can enhance temperature change during phase transition, enabling potential magnetic refrigeration applications.

Contribution

It introduces a method to control the magnetocaloric effect via electric fields in a magnetoelectric composite, combining piezoelectric and magnetic properties for tunable cooling.

Findings

Electric voltage of 100 V increases adiabatic temperature change by 0.2 K.

Finite element calculations show electric fields induce ~3 MPa stress inside PZT.

Magnetocaloric effect contribution depends linearly on electrical voltage at low pressures.

Abstract

The possibility of electric field control of magnetocaloric effect through quasi-isostatic compression as a result of the converse piezoelectric effect was demonstrated on cylindrical type magnetoelectric composite MnAs/PZT. It was shown that an electric voltage of 100 V corresponding to an electric field of E ~0.3 kV/mm applied to the walls of the piezoelectric component PZT of the MnAs/PZT composite contributes to an increase in the maximum adiabatic temperature change by 0.2 K in the temperature range of the magnetostructural phase transition of MnAs ~317 K at magnetic field change of 1.8 T. Calculations using the finite element method have shown that an electric field voltage of 100 V is capable of creating a quasi-isostatic mechanical stress in the region inside a cylindrical PZT tube of ~3 MPa. Moreover, in the region of weak pressures up to 10 MPa, the contribution to the MCE from piezo compression linearly depends on the electrical voltage that can be used for control the MCE