Noise characteristics of CoCrTa/NiFe perpendicular recording media

The authors show that the spike-noise peak frequency is from 20 to 40 kHz at a velocity of 13 m/s. This frequency does fall wide of the frequency band of data, so it can be removed by a high pass filter. It is also shown that storage-layer noise is the greater part of the total medium noise. The low noise medium was used with a narrow pole contact recording head. A total signal-to-noise ratio of over 20 dB at a recording density of 1 Gb/in/sup 2/ (17 kTPI, 60 kBPI) was obtained.<
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