Transport properties and micromagnetic modeling of magnetic nanowires with multiple constrictions

Ni nanowires were fabricated by electrochemical deposition in the pores of alumina and polycarbonate membranes, with the diameter around 200 nm and 30 nm, respectively. To study the magnetic and electrical properties of Ni nanowires, individual nanowires were selected and connected with metal electrodes. Single and multiple constrictions were formed on the nanowires by FIB. The wires were further thinned using oxygen plasma oxidation and chemical etching. Magnetoresistance curves were studied and compared before and after FIB trimming, oxidization and chemical etching. 3-D micromagnetic modeling was used to simulate the magnetoresistance of the nanowires with and without constrictions.