Effect of angular biasing on the magnetic performance of spin-valve devices

Abstract

In spin-valve devices, hard magnets are placed at both ends of the sensor to suppress Barkhausen noise. As a consequence, the signal amplitude decreases. We have shown that, by initializing the magnets in a direction other than along the free layer easy axis, it is possible to increase the magnetoresistance ratio by more than a factor of 2. The ΔR/R of similar devices without permanent magnets cannot be reached by this method. This angular initialization may have technological applications.