Temperature dependence of coercivity in Co-based longitudinal thin-film recording media

The coercivity of Co-based (CoCrTa and CoCrPt), disk media was found to depend on temperature. The thinner the film, the smaller the switching unit (KuV), and the larger dHc/Hc dT. dHc/HcdT for CoCrTa (400 Å) on different underlayers or intermediate layers is generally larger than that of CoCrPt (400 Å) on different underlayers or intermediate layers. The temperature dependence of coercivity in Co-based disk media is caused by the temperature dependence of crystalline anisotropy of Co and small switching unit of the media.