Electrostatic extension of magnetic proximity effect in La_0.7Sr_0.3MnO₃

Magnetic proximity effects are typically limited to a few nanometers due to the short-range nature of the underlying magnetic interactions. Here, we use off-axis electron holography to reveal an electrostatically induced long-range magnetic proximity effect that extends over a distance of 40 nm at a ferromagnetic/paramagnetic interface in La0.7Sr0.3MnO3. We show that this behavior results from carrier diffusion and drift across the interface, which changes the Mn3+/Mn4+ ratio and hence the local Curie temperature and density of magnetic moments.