Discrete step stabilization of narrow-track amr read sensors

Abstract

A method and system are provided for implementing discrete step stabilization of AMR read sensors in tape or disk drives. In one implementation, a plurality of discrete step stabilizers and AMR read sensor elements are arranged with a rotational symmetry coupled with a plane inversion for an odd number of steps, and no inversion for an even number of steps. Preferably, the steps are oriented at 45 degrees, or approximately parallel to the desired bias direction. For relatively narrow track widths (e.g., approximately 5 microns), the edges of the sensor element nearest the permanent magnets are especially important to stabilize. Therefore, in one implementation, an edge of a stabilizer preferably intersects the edge of the sensor element at one half of the stripe height. Also, the rising and falling edges of the stabilizers do not always have the same slope. In order to compensate for the different slopes of a stabilizer's edges, the rising and falling edges of a stabilizer's pattern are interchanged by a 'stabilizer phase' transformation to produce the complement (phase conjugate) of the stabilizer pattern. As such, if a single rising edge of a stabilizer pattern intersects the center of a sensor element, the 'stabilizer phase' transformation changes this structure to a single falling edge that intersects the center of the sensor element.