Patent ID: 6819530
Filing Date: 2004-11-16
Classification: B82Y,G11B

Abstract:
A magnetic head assembly having a head surface for facing a magnetic medium comprising:first and second CPP sensors; each CPP sensor including a ferromagnetic free layer which has a magnetic moment that is oriented substantially parallel to the head surface and is free to rotate in response to a signal field from a magnetic medium; each free layer having major planes that are perpendicular to the head surface and a stripe height that extends normal to said head surface into the magnetic head assembly; a nonmagnetic electrically conductive bias layer located between the first and second CPP sensors with major planes parallel to the major planes of the free layers and extending in a direction away from the head surface into the head assembly beyond the stripe heights; ferromagnetic first and second shield layers; the first and second CPP sensors and the bias layer being located between the first and second shield layers; the first and second shield layers being electrically connected to the first and second CPP sensors respectively for conducting first and second currents respectively through the first and second CPP sensors perpendicular to the major planes of the free layers to the bias layer; and the bias layer being electrically connected to the first and second CPP sensors and sized so that the first and second currents can flow through the bias layer perpendicular to the head surface to cause a biasing field that biases the magnetic moments of the free layers antiparallel with respect to one another.