Perpendicular recording near 100 Gb/in/sup 2/

Abstract

Theoretical analyses have projected perpendicular recording capable of achieving ultimate areal densities greater than longitudinal recording systems. For perpendicular recording to supplant longitudinal recording, laboratory demonstrations will need to be made which intercept or exceed the areal densities achieved by state-of-the-art longitudinal recording demonstrations. Recent demonstrations have come close to eliminating the gap between these technologies. In this paper, recording experiments at areal densities in the 60 to 100 Gb/in 2 range will be described. It will be shown that the head field from conventional single-pole writers is not well localized to the data track and that if the media do not have sufficiently high nucleation thresholds, this fringe field will gradually erase data on the adjacent track if the track pitch is too aggressive. Extension of this technology to densities of the order of 1 Tb/in 2 will require heads that reduce the extent of the fringe field without sacrificing available on-track field.Index Terms-Magnetic recording high-density recording, magnetic recording systems integration, superparamagnetic limit.

Symmetry breaking of adjacent tracks in perpendicular recording system

“…the solid lines in figures 5(a) and 5(b) remain flat. (2) When the read width is W r = 40 nm = 2W/3, there is no conspicuous enhancement of track-edge noise in T1 if the guard-band width is larger than half of the track width, as seen in the dotted line in figure 5(a), which agrees well with previous experiments [6,16] and is similar to the PW 50 results for the longitudinal recording in [17]. (3) The total noise power of T1, with a read width W r = 60 nm, varies little with track pitch, as shown in the dashed line in figure 5(a).…”

“…Experimental studies have been carried out to investigate ATI in perpendicular recording [6][7][8]. Stray fields under different portions of the write head have been studied and a way of selecting an optimal write current has been proposed in [7].…”

Finite-element model analysis of single-pole-type head for 1 Tbit/in/sup 2/

“…Conceptual studies for areal densities of 1 Tbit/in have also been shown [2]- [5]. To achieve an areal density of 1 Tbit/in , it is necessary to reduce the side-writing field as well as obtain a large recording field strength with a narrow-track SPT heads as predicted in [6].…”