High frequency sensitivity in single-pole head

The high-frequency sensitivity of a main-pole-driven single-pole head in combination with a Co-Cr/Ni-Fe double-layer medium has been studied. The linear density responses for the reproduced signal were measured for relative velocities of 5 and 10 m/s. A significant difference in the output for different relative velocities was found at densities in excess of 10 kFRPI. This is attributed to the fact that, even at the same linear recording density, the different speeds mean different recording frequencies. Since the recording frequency at 10 m/s is twice as high as that at 5 m/s, the high-frequency sensitivity declines correspondingly. Results are also reported that indicate that choosing the appropriate ferrite material and/or modifying the head construction in such a way that the effect of the magnetic properties of the ferrite components is diminished will lead to the perpendicular magnetic heads with enhanced sensitivity at high frequencies.