Small -dH/sub c//dT characteristics of CoPt granular and thin film recording media

The temperature dependence of the coercivity H/sub c/ was measured for CoPt-based thin film, CoPt-SiO/sub 2/ granular film and CoCr-based thin film recording media. All the samples showed a linear decrease in H/sub c/ with temperature, -dH/sub c//dT. It is found that CoPt-based media have smaller -dH/sub c//dT values than CoCr-based one. This means that CoPt-based media have good stability for archival and read/write characteristics at elevated temperatures. From a theoretical discussion, it is also found that CoPt-based thin film and granular media with small activating magnetic moment value are expected to have smaller recording coercivity than CoCr-based media.