Nanoscale manipulation of magnetic domains by strain-induced proximity*

Coupling between lattice and spin degrees of freedom without the use of magnetic fields allows for efficient spintronic devices. Hybrid nanostructures composed of a vanadium oxide undergoing a first-order, structural phase transition (SPT) and a ferromagnet (FM) offer a promising route to control of magnetism by strain-induced proximity. Up to 500% coercivity increase was found in Ni/V₂O₃ bilayers in a very narrow T range. By synchrotron-based X-ray microscopy we show a reconfiguration of the FM domain pattern across the V₂O₃ SPT. The lateral correlation length of the Ni domains shows a significant increase at the SPT and a broad distribution of the local transition temperatures is found. These findings are supported by static and dynamic magnetometry measurements and micromagnetic simulations. All the above point to nanoscale phase coexistence of two Ni magnetic anisotropies induced by interfacial stress transfer across the SPT of V₂O₃. This allows to manipulate magnetic domains at the nanoscale and pursues to engineer coercive fields for novel data storage architectures based on straintronics.