Reduction in critical current of current-induced switching in exchange-biased spin valves

Abstract

The current-induced magnetization reversal (CIMR) effect in nanosized exchange-biased spin valves (EBS) of IrMn/Co(1)/Cu/Co(2) is investigated. The CIMR is studied at RT. With our EBS structure, the critical current can be lowered to 7.5 X 10(6) A/cm(2), which is rather smaller than that in the conventional simple spin valves (SS) Co(1)/Cu/Co(2). This effect can be attributed to the enhancement of spin transfer efficiency by using antiferromagnetic pinning layer in that structure. However, the absolute change in total resistance of EBS, in comparison to that of SS with similar layer thickness, is not increased, as the nearly unpatterned fixed Co layer is pinned. The results are discussed in terms of current induced spin transfer and current induced thermal activation. (c) 2005 American Institute of Physics.