American Institute of Physics, Journal of Applied Physics, 4(115), p. 043910
DOI: 10.1063/1.4863306
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We present a remarkable enhancement by 300% of the exchange-bias field at room temperature, without affecting the coercivity value, via optimum magnetic annealing (250 °C/3 kOe) in ion-beam sputtered FeMn(30 nm)/NiFe(10 nm) bilayers. This specific behavior has been attributed to a higher degree of γ-FeMn(111) orientation that offers more interfacial FeMn moments to get pinned with the moments of the adjacent NiFe layer. Unlike the absence of training effect at room temperature, a pronounced training effect and an accompanying magnetization reversal asymmetry are evidenced upon field cooling below 50 K due to the presence of biaxial exchange induced anisotropy across the interdiffused FeMn/NiFe interface. The present findings not only have technological significance but also are of relevance to the understanding of interfacial spin disorder and frustration in these exchange-biased systems.