EVALUATION OF DOUBLE-LAYERED MAGNETIC RECORDING MEDIUM COMPOSED OF PERPENDICULAR AND LONGITUDINAL ANISOTROPY LAYERS

A double-layered (DL) medium composed of a CoNiReP perpendicular aniso tropy top layer (0.20 mum thick) and CoP longitudinal anisotropy under layer (0.05 mum thick) was fabricated and its recording characteristic s were investigated with a combination of a ring-type head. The reprod uced voltage of the DL medium was enhanced to be larger than that of t he simple summation of the reproduced voltage of the CoNiReP single-la yered medium and that of the CoP one. Moreover, the reproduced wavefor m of the DL medium showed a single peak pulse and it did not change ev en at higher recording magnetomotive force (MMF). These results sugges t that the reproduced voltage enhancement comes from the phase synchro nization effect even at higher recording MMF.