Asymmetrical magnetization processes induced by compositional gradients in ferromagnetic nanowires

Abstract

Electrodeposited nanowires are an excellent scenario to study and control magnetic domain wall motion in nanostructures. In particular, the introduction of local changes in composition during the growth procedure has been proven to be very efficient for controlling the magnetization dynamics. In this work, we show the possibility of introducing compositional gradients in FeNi electrodeposited nanowires by gradually changing the Fe/Ni ratio along their axis. These compositional gradients produce an asymmetrical landscape for domain wall motion which is reflected in asymmetrical magnetization processes under an applied magnetic field. By studying nanowires with different compositional gradients we were able to correlate composition and magnetic asymmetry. Our results pave the way towards full control of the movement of domain walls along the nanowires.