Often this phase transition is accompanied by an important variation of the material’s volume. Authors make use of the coupling between magnetism and volume to control at the nanoscale antiferromagnetic and ferromagnetic competing phases at the phase transition of metamagnetic film. The method is as simply as applying pressure with a needle. As the needle is nanometric authors induce an irreversible phase transition at the nanoscale. This allows to have nano-antiferromagnetic islands embedded in an ferromagnetic matrix. Authors show that if this process is repeated across the film the phase change can be induced also across large areas. The method should allow to engineer complex nanometric antiferromagnetic/ferromagnetic spintronic devices without requiring advanced lithography tools and can allow to study in detail new phenomenology appearing at the antiferromagnetic/ferromagnetic domain walls.

Local manipulation of metamagnetism by strain nanopatterning
Michael Foerster, Enric Menéndez, Emerson Coy, Alberto Quintana, Carles Gómez-Olivella, Daniel Esqué de los Ojos, Oriol Vallcorba, Carlos Frontera, Lucia Aballe, Josep Nogués, Jordi Sort* and  Ignasi Fina * 
Mater. Horiz., 2020, Advance Article.
DOI:10.1039/D0MH00601G

Local manipulation of metamagnetism by strain nanopatterning