Large Longitudinal Magnetoelectric Coupling in NiFe₂O₄–BaTiO₃Laminates

In contrast to the Pb-based magnetoelectric laminates (MELs), we find in the BaTiO 3 and NiFe 2 O 4 laminates (number of layers n =5–25) that the longitudinal magnetoelectric (ME) voltage coefficient α E33 becomes much larger than the transverse one due to preferential alignment of magnetic moments along the NiFe 2 O 4 plane. Moreover, upon decreasing each layer thickness down to 15 µm, we realize enhanced α E33 up to 18 mV/(cm·Oe) and systematic increase of the ME sensitivity in proportion to n to achieve the largest in the Pb-free MELs (400×10 -6 V/Oe), thereby providing pathways for tailoring ME coupling in mass-produced, environment friendly laminates.