Stress effects on the magnetic properties of FeMn and NiMn spin valves

The effects of stress on exchange coupling field, H-ex, coercivity, H-c, and pinning field, H-p, in NiFe/FeMn and NiFe/NiMn exchange-biased spin valves deposited using ion beam sputtering have been examined. The samples were uniaxially strained (compressive and tensile) along the easy and hard axis directions. The hysteresis loops of the stressed spin valves were measured in situ along the easy and hard axes using a vibrating sample magnetometer. It is found that the NiFe/FeMn spin valves are more susceptible to the effects of stress than NiFe/NiMn, with the most significant effects occurring along the hard axis. In addition to being less susceptible to the effects of stress, NiFe/NiMn spin valves displayed more isotropic effects to the stress along the easy and hard axis directions.