Abstract: A magnetic sensor includes a sensor stack having a first magnetic portion, a second magnetic portion, and a barrier layer between the first magnetic portion and the second magnetic portion. At least one of the first magnetic portion and the second magnetic portion includes a multilayer structure having a first magnetic layer having a positive magnetostriction adjacent to the barrier layer, a second magnetic layer, and an intermediate layer between the first magnetic layer and the second magnetic layer. The magnetic sensor has an MR ratio of at least about 80% when the magnetic sensor has a resistance-area (RA) product of about 1.0 ?·?m2.

Abstract: A sensor includes a sensor stack and a layer of high resistivity material having a precursor within the sensor stack. When a current is applied at the precursor, a current confining path is formed through the layer of high resistivity material at the precursor.

Abstract: A magnetoresistive (MR) sensor having a decreased electrical profile due to a confining of the device sense current within a conductive nanoconstriction. The MR sensor includes a giant magnetoresistive (GMR) stack and a layer of high resistivity material within the GMR stack. The layer of high resistivity material includes a nanoconstriction precursor. When a punch current is applied at the nanoconstriction precursor, a conductive nanoconstriction is formed through the layer of high resistivity material at the nanoconstriction precursor.