M-R element width and thickness effects on reverse switching thresholds

During the reverse reading of a `one´ for a magnetoresistive memory element, one or two stable configurations of the magnetization can exist involving smaller and larger rotations of the magnetization. In hostile radiation environments, the two-state condition is undesirable because restoration after reading may occur by wall motion. An analysis was performed on the thickness, separation, and element width dependence of the field boundary between the one and two stable condition. The boundary sense field increased as an inverse square of element width and approximately as the product of layer thickness and separation. Elements can be designed to conveniently operate in the single state mode