Efficient thermal energy harvesting using nanoscale magnetoelectric heterostructures

TL;DR

This paper proposes a theoretical method for efficient room-temperature thermal energy harvesting using magnetoelectric multiferroic heterostructures, which outperform pure ferroelectrics due to their coupled electric and magnetic properties.

Contribution

It introduces a novel theoretical framework combining ferroelectric and magnetic dynamics to optimize energy harvesting in multiferroic composites.

Findings

Multiferroic heterostructures show higher efficiency than pure ferroelectrics.

External fields can steer the heat engine operation.

Potential applications in low-energy devices and cooling technologies.

Abstract

Thermomechanical cycles with a ferroelectric working substance convert heat to electrical energy. As shown here, magnetoelectrically coupled ferroelectric/ferromangtic composites (also called multiferroics) add new functionalities and allow for an efficient thermal energy harvesting at room temperature by exploiting the pyroelectric effect. By virtue of the magnetoelectric coupling, external electric and magnetic fields can steer the operation of these heat engines. Our theoretical predictions are based on a combination of Landau-Khalatnikov-Tani approach (with a Ginzburg-Landau-Devonshire potential) to simulate the ferroelectric dynamics coupled to the magnetic dynamics. The latter is treated via the electric-polarization-dependent Landau-Lifshitz-Gilbert equation. Performing an adapted Olsen cycle we show that a multiferroic working substance is potentially much more superior to sole ferroelectrics, as far as thermal energy harvesting using pyroelectric effect is concerned. Our proposal holds promise not only for low-energy consuming devices but also for cooling technology.