Engineering issues study of ring-shaped head recording on single layered perpendicular media

Abstract

This article presents results of experimental study on the engineering issues of using ring-shaped thin-film head and single layered perpendicularly orientated media for high density magnetic recording. Comparing with the experiment conducted with longitudinal media, this combination is of smaller sensitivity of its nonlinear transition shift to the variation of the head-disk spacing, smaller writing current for saturation recording even if the media coercivity is 25% higher than that of the longitudinal counterpart. Furthermore, the width of its erasure band is quite comparable to the case using longitudinal media, if the writing current is selected properly. On the other hand, the combination is of slightly larger asymmetry of its track profile and slightly more sensitive to the skew angle increment, if the anisotropic magnetoresistive head is used for reading.

Low NLTS approach: Perpendicular/Longitudinal composite media

“…The possible reasons include: the perpendicular media may switch at slower speeds compared with the longitudinal media [7], and may undergo larger dynamic coercivity changes. Alternatively, the perpendicular layer is more sensitive to variations of the head-disk spacing [8], [9].…”