Pseudo-spin-valve with L10 (111)-oriented FePt fixed layer

Abstract

Recently we proposed a spin torque oscillator where the fixed layer has its magnetization easy-axis tilted with respect to the film plane to simultaneously achieve zero-field operation and high output power [Y. Zhou, C. L. Zha, S. Bonetti, J. Persson, and J. Åkerman, Appl. Phys. Lett. 92, 262508 (2008)]. Here we take the first step toward the realization of this device and fabricate successfully a pseudo-spin-valve using an L10 (111)-oriented FePt fixed layer with tilted magnetocrystalline anisotropy. A total magnetoresistance (MR) of 0.86% is experimentally observed for the standard pseudo-spin-valve of the L10 FePt/Cu/NiFe structure in applied fields up to 1.5 T. While part of the MR may originate from the FePt film alone, the dominating part of MR correlates with switching of the NiFe free layer.