Title: Micromagnetic Simulations for Coercivity Improvement through Nano-Structuring of Rare-Earth Free L1$_0$-FeNi Magnets,
Abstract: In this work we investigate the potential of tetragonal L1$_0$ ordered FeNi
as candidate phase for rare earth free permanent magnets taking into account
anisotropy values from recently synthesized, partially ordered FeNi thin films.
In particular, we estimate the maximum energy product ($BH$)$_\mathrm{max}$ of
L1$_0$-FeNi nanostructures using micromagnetic simulations. The maximum energy
product is limited due to the small coercive field of partially ordered
L1$_0$-FeNi. Nano-structured magnets consisting of 128 equi-axed, platelet-like
and columnar-shaped grains show a theoretical maximum energy product of 228
kJ/m$^3$, 208 kJ/m$^3$, 252 kJ/m$^3$, respectively.