Giant sharp and persistent converse magnetoelectric effects in multiferroic epitaxial heterostructures

Magnetoelectric coupling1,2 between magnetic and electrical properties presents valuable degrees of freedom for applications. The two most promising scenarios are magnetic-field sensors3 that could replace low-temperature superconducting quantum interference devices, and electric-write magnetic-read memory devices that combine the best2 of ferroelectric and magnetic random-access memory. The former scenario requires magnetically induced continuous and reversible changes in electrical polarization. These are commonly observed, but the coupling constants thus obtained are invalid for data-storage applications, where the more difficult to achieve4,5 and rarely studied magnetic response to an electric field is required. Here, we demonstrate electrically induced giant, sharp and persistent magnetic changes (up to 2.3×10−7 sm−1) at a single epitaxial interface in ferromagnetic 40 nm La0.67Sr0.33MnO3 films on 0.5mm ferroelectric BaTiO3 substrates. X-ray diffraction confirms strain coupling via ferroelastic non-180◦ BaTiO3 domains. Our findings are valid over a wide range of temperatures including room temperature, and should inspire further study with single epitaxial interfaces