Angular dependence of exchange bias in Mn80Ir20/Co60Fe20B20 bilayers

作者：Yang J^*; Cardoso S; Freitas P P; Devolder T; Ruehrig M

来源：Journal of Applied Physics, 2011, 109(7): 07D704.

DOI：10.1063/1.3537951

We investigated the dynamics of exchange bias field H-EB of Mn80Ir20 (80 angstrom)/Co60Fe20B20 (110 angstrom) thin films at temperatures of 300, 375, and 450 K by means of vector network analyzer ferromagnetic resonance. The results show that H-EB deduced from the resonance frequencies along the hysteresis loop varies significantly and that this large variation is due to thermally activated reversal of the antiferromagnetic domains during measurements. Furthermore, the results of H-EB as a function of angle show that H-EB is mainly unidirectional with fewer contributions from the uniaxial anisotropy as evidenced by the fits to the data based on the Fourier cosine series. It is also found that the symmetries of H-EB at temperatures higher than 300 K decreases compared with that at 300 K.

• 出版日期2011-4-1