EXPERIMENTAL-STUDY OF THERMAL DECAY IN HIGH-DENSITY MAGNETIC RECORDING MEDIA

The thermal decay of written bits in CoCrPt/CrTi thin film media for h igh density longitudinal magnetic recording is examined using a magnet oresistive head at room temperature. A decay in signal output over tim e is observed for the media with a thin magnetic layer less than about 14 nm thick and the media noise increases. The thermal stability fact or Ku.V/k.T of these media is estimated to be less than about 100. The signal decay and noise increase are more serious at higher linear rec ording densities. These results are consistent with the results of a m icromagnetic simulation taking into account the thermal aftereffects. These characteristics suggest that media with a large magnetic anisotr opy constant Ku will be required to realize high storage densities of over 10 Gb/in(2).