Transverse recording using thin film recording heads

This paper presents the results of an investigation of a high density magnetic recording technique utilizing a thin film recording head and a transverse mode of recording on thin media. The significant results of this investigation are as follows. 1) Densities as high as 18 500 transitions per inch were experimentally written in a 300-Å thick FeCr medium having an H
c
of 70 oersteds. 2) These densities were written with a thin film, vapor-deposited, recording head having a MATED-FILM® structure with a 0.4-mil etched gap. 3) Track widths of 1-mil on 2-mil centers were experimentally achieved. 4) Optical readout of a 0.2-mil wide transition (width of beam) region corresponding to 5000 transitions per inch was achieved using a laser beam and a linear motion transport system under ideal experimental conditions. 5) The magnetic field from the Néel wall separating recording domains was detected using a MATED-FILM Etched Gap head making this a possible readout method. Maximum achieved linear bit densities as a function of recording media coercivities are given.