Understanding the mechanisms of magnetoelectric (ME) coupling within multiferroic structures is paramount from a fundamental as well as an applied point of view. We report here that the magnetoelectric properties, as well as the magnetization, of BaTiO3-BiFeO3 superlattices can be tuned by varying the BiFeO3 layer thickness. The magnetoelectric voltage coefficient (αME) reaches its maximum of 60.2 Vcm−1Oe−1 at 300 K, one of the highest values reported so far, for a sample with a BiFeO3 thickness of 5 nm and a BaTiO3 thickness of 10 nm. To gain deeper insight into the increased magnetoelectric coupling, and both the local and macroscopic magnetic properties, samples with varying BiFeO3 thicknesses have been investigated. Correlations were established between the hyperfine field (HFF), the magnetoelectric voltage coefficient and the magnetization. The possible mechanisms responsible for the strong magnetoelectric coupling are discussed.
@article{arxiv.2303.08493,
title = {Impact of magnetization and hyperfine field distribution on high magnetoelectric coupling strength in BaTiO$_3$-BiFeO$_3$ multilayers},
author = {Johanna K. Jochum and Michael Lorenz and Haraldur P. Gunnlaugsson and Christian Patzig and Thomas Höche and Marius Grundmann and André Vantomme and Kristiaan Temst and Margriet J. Van Bael and Vera Lazenka},
journal= {arXiv preprint arXiv:2303.08493},
year = {2023}
}