Multi-track magnetoresistive head design technique for high density tape recording

Both symmetrization of isolated readback pulses and feed-through suppression are investigated in multi-track magnetoresistive (MR) heads shielded with a magnetic film and substrate. The influence of MR head parameters on isolated readback pulse symmetry is analyzed theoretically using a Green function and the reciprocity theorem. The theoretical results show that an isolated readback pulse can be sufficiently symmetrized by optimizing such MR head parameters as film shield thickness and gap length. Feed-through characteristics from a thin film write head to the MR head are analyzed experimentally. Feed-through is shown to occur through a one-turn-loop formed by the MR element and its leads. As a result, a new MR head arrangement is proposed, which is characterized by two divided MR elements and produces a feed-through suppression of 32 dB.