高周波記録に及ぼす媒体ダンピング定数αの影響  [in Japanese] Influence of Damping Constant α on Recording Characteristics at High Frequencies  [in Japanese]

The influence of the damping constant α on recording characteristics at high frequencies was simulated by using the Langevin equation, with the condition that the head field rise time is constant. In the frequency range up to 190 MHz the signal outputs for α=1 and α=0.05 are same. On the other hand, in the higher-frequency range over 190 MHz, where the head field decreases before it reaches the maximum value, the signal outputs for α=0.05 are larger than those for α=1.0. This is because the critical switching field depends on the damping constant α and it decreases with a lower value of α.