Finite-size effects on the magnetoelectric response of field-driven ferroelectric/ferromagnetic chains

TL;DR

This paper investigates how finite size influences the magnetoelectric response in one-dimensional ferroelectric/ferromagnetic chains, revealing size-dependent control of magnetization and polarization through external fields.

Contribution

It provides a theoretical analysis combining Monte-Carlo and coupled equations to understand size effects on magnetoelectric switching in multiferroic chains.

Findings

Thin chains (up to 10 sites) can have their magnetization and polarization fully reversed by external fields.

Larger chains exhibit limited magnetoelectric control, only allowing partial switching.

Finite-size effects significantly impact the magnetoelectric response in multiferroic chains.

Abstract

We study theoretically the coupled multiferroic dynamics of one-dimensional ferroelectric/ferromagnet chains driven by harmonic magnetic and electric fields as a function of the chain length. A linear magnetoelectric coupling is dominated by the spin-polarized screening charge at the interface. We performed Monte-Carlo simulations and calculations based on the coupled Landau-Lifshitz-Gilbert and Landau-Khalatnikov equations showing that the net magnetization and the total polarization of thin heterostructures, i.e. with up to ten ferroelectric and ferromagnetic sites counted from the interface, can be completely reversed by external electric and magnetic fields, respectively. However, for larger system solely a certain magnetoelectrical control can be achieved.