%0 Journal Article %A Romera Rabasa, Miguel Álvaro %A Muñoz García, Mercedes %A Sánchez, P. %A Aroca, C. %A Prieto, J. L. %T Influence on the magnetoresistance of a spin valve due to the insertion of an ultrathin Gd layer in the free layer %D 2009 %@ 0021-8979 %U https://hdl.handle.net/20.500.14352/95940 %X The effect of inserting an ultrathin Gd layer (1-2 nm) in the free layer of a Permalloy-based spin valve has been investigated. In the current in-plane configuration, samples with Gd show a reduced magnetoresistance (MR) value, which tends to zero as Gd gets closer to the nonmagnetic spacer, although good MR values can be sustained when Gd is more than 5 nm away from the spacer. We studied also the effect of adding thin Fe layers around Gd in order to avoid Gd diffusion within the Permalloy. Samples with an Fe/Gd/Fe trilayer inserted in the free layer show some improvement at low temperatures over those without Fe, although the Fe introduces some detrimental additional roughness. (C) 2009 American Institute of Physics. [DOI: 10.1063/1.3173580] %~