MICROMAGNETICS OF GMR MULTILAYER SENSORS AT HIGH-CURRENT DENSITIES

The effect of internal sense current fields on the 2-D micromagnetics of an idealized GMR multilayer stripe of 2N magnetic layers exchange coupled across 2N-1 intermediate nonmagnetic conduction layers is considered theoretically. Both antiferromagnetic and biquadratic interlayer exchange coupling terms are included. The magnetization distribution due to sense current self-fields is approximated analytically. Numerically generated external field transfer curves at variable current density, J, compare wed to experiments with test devices of NiFeCo-Cu. Loss in head performance due to self-bias effects in high J, low exchange-coupled GMR multilayer devices likely characteristic of future high density MR reproduce heads is examined.