Magnetoelasticity and the spin rotation transition in cobalt

Abstract

We study the spin reorientation process in cobalt using capacitance dilatometric measurements of the strain along the a- and c-axes of a single crystal and then apply a phenomenological theory of magnetostrictive interactions together with a theory of spin reorientation. We find no evidence of singularities in the behaviour at either of the temperatures at the beginning and end of this process. We calculate the temperature dependence of the magnetoelastic fourth-order single-ion anisotropy coefficient K4, and draw attention to the importance of higher order terms in the anisotropy. PACS Nos.: 74.25.Ha, 75.30.Gw, 75.50.Cc, 75.80.+q