Anisotropic Magnetoresistance of Epitaxial Grown CoFe Thin Films on Flexible Mica and Rigid MgO Substrates

This study investigates the correlation of anisotropic magnetoresistance (AMR) to the crystal structure, epitaxial relationship, and magnetic properties of CoFe films on both rigid MgO and flexible mica substrates. The AMR ratio is approximately 1.6% for CoFe films on a flexible mica substrate, which is lower than that on MgO substrate of about 2.5% under growth temperature 400°C. The angular dependence of applied magnetic field of AMR ratio to the applied current directions along CoFe[100] and CoFe[110] on MgO and mica substrates are totally different. It could be due to that the epitaxial CoFe film on MgO substrate is in one domain, while three symmetric CoFe domains on mica partly smeared out the in-plane anisotropy with less significant preferred orientation.