Synthesis and magnetism of modulated FeCo-based nanowires

Abstract

FeCo based nanowire arrays have been proposed for different applications as high-density magnetic storage or sprintronics. Depending on the application different magnetic properties are required and the electrochemical techniques are low-cost routes to tailor them, by tuning the nanowires composition and geometry. In this work two different types of nanowires are studied: multisegmented nanowires and nanowires with modulated diameter. The magnetic properties of multisegmented [FeCoCu(y)/Cu(x)]10 nanowire arrays have been studied considering different Cu layer thicknesses (x) and FeCoCu segment lengths (y). The obtained results show that the hard magnetic properties of these nanowire arrays present a higher coercivity and remanence comparing to the continuous nanowires, for thicker Cu layers and shorter FeCoCu segments. On the other hand, for the nanowires with modulated diameter it has been stated that the magnetization reversal process takes place by a vortex domain wall and with the tailored modulations along the nanowire it is possible to induce the domain wall pinning. This opens the possibility of controlling the domain wall motion along magnetic nanowires.