Magnetoelectric Bi3.15Nd0.85Ti3O12–NiFe2O4 bilayer films derived by a SOL–GEL method

Magnetoelectric Bi3.15Nd0.85Ti3O12–NiFe2O4 (BNT–NFO) bilayer films were deposited on Pt/Ti/SiO2/Si(100) substrates by a simple SOL–GEL method and spin-coating process with different growth sequences of BNT and NFO yielding the following layered structures: BNT/NFO/substrate (BNS) and NFO/BNT/substrate (NBS). Such heterostructures present simultaneously strong ferroelectric and ferromagnetic responses, as well as magnetoelectric effects at room temperature. BNS thin films showed larger ME voltage coefficient than NBS films, revealing that the layer sequences have a significant influence on the magnetoelectric coupling behavior of these bilayer structures, which may be caused by a interfacial effect.