Abstract
In perpendicular magnetic recording utilizing double layer media, demagnetization of recorded bit by a single pole head, which is called "head induced erasure", is one of the issues. This is caused by the strong head-to-medium magnetic interaction between the main pole of the single pole head and the underlayer of the double layered perpendicular medium. In this report, this head induced erasure by stray field was measured for various heads and media combination. Permeability of the underlayer and the structure of the head improved the demagnetization. A computer simulation based on the Finite Element Method was carried out, and supported these tendencies obtained by the experiments.
