Dynamic micromagnetic write head fields during magnetic recording in granular media

Magnetic recording at fast data rates requires write heads with rapid rise times of the magnetic flux during the write process. We present three-dimensional (3-D) micromagnetic finite-element (FEM) calculations of an entire ring head (including 3-D coil geometry) during the writing of magnetic bits in granular media. The calculation of the obtainable flux rise times takes into account the current rise in the coils, the magnetization processes in the yoke, the magnetization processes in the pole regions near the gap, as well as the magnetization dynamics in the magnetic recording media. The simulations demonstrate how input current profiles translate into magnetization processes in the head and media during writing.