Dynamic response of domain walls on the air-bearing surface of thin-film heads

Abstract

The domain configurations on the air-bearing surface (ABS) of inductive thin-film recording heads were studied. It was found that, instead of being a single domain structure, the ABS of a thin-film head usually has multidomains. The direction of the domain walls is neither parallel nor perpendicular to the gap plane. The magnetization was found to be in the plane of the ABS along the track width, with the magnetizations on the two sides of the domain walls either "head-to-head" or '"tail-to-tail." The domain walls are slanted in order to spread the magnetic charges along the wall over a larger region, thereby reducing magnetostatic energy in this configuration. The responses of the domain walls are not all in phase, and they are generally out of phase with the rotational process along the gap edge. The magnetization configuration on the ABS and in the throat and the sloped region were investigated in one. head and correlated with the domain walls on the ABS.

High frequency magnetization response observed at the air-bearing surfaces of thin film heads

“…Utilizing the magneto-optic polar Kerr effect, averaged dynamic magnetization reversals in the component perpendcular to the ABS were observed via SKEM [6]. 36-turn thin film inductive heads with P2W=6 pm, PlW=7.5 pm, PlT=P2T=3.5 pm and gap=0.27 pm as well as MR write heads with P2W=3.5 pm, P2T=3.5 pn, gap=0.4 pm and 15 turns were selected for study.…”