Analytical expressions for shielded MR head response

Recording mechanism of perpendicular recording was examined using analytica l expression of shielded AMR/GMR head response. Pulse shape, roll-off perfo rmance, and noise spectra were reasonably explained by the calculated head transfer functions. Comparison with the calculation based on the formulae s howed several fundamental characteristics of perpendicular recording: no la rge media noise at low frequencies in magnetic sense, but simply due to a r eflection of a head transfer function: no severe resolution degradation: ne gligible noise power directly arisen from soft magnetic underlayer. This me thod will provide a convenient design tool for perpendicular magnetic recor ding.