Correlation of Exchange Bias and Angle on Applied Perturbation Field and Anti-Ferromagnetic Spins

DOI: 10.4236/jmp.2011.210148   PDF   HTML   XML   3,603 Downloads   6,578 Views   Citations


High-resolution anisotropic magneto-resistance measurement (AMR) was used to detailed study the training effect in exchange biased CoO/Co bi-layer. The sample was cooled to 10 K from room temperature in the magnetic cooling field of 4000 Oe. Then we used 1500 Oe declined perturbation field to pin the magnetization orientation of the FM layer. The perturbation field forms certain angle Θ with the cooling field direction in-plane to re-induce the untrained state. The dependence of the untrained state on the angle between the direction of perturbation field and cooling field has been investigated. The AMR results reveal that the re-induced degree of untrained state is strongly correlated to the angle Θ. The exchange bias field HE for different Θ has been determined from the AMR results, which is in apparent agreement with the Meiklejohn-Bean model. The recover degree of untrained state is the largest when the angle is 75°, which is different from the traditional view point that untrained state should be the maximum when it is perpendicular. The training effect is related to the FM spin orientation, which can induce the change of the interfacial AFM spin reorientation with different angles.

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X. Fu, G. Cao, Y. Gao, Z. Wu and J. Zhang, "Correlation of Exchange Bias and Angle on Applied Perturbation Field and Anti-Ferromagnetic Spins," Journal of Modern Physics, Vol. 2 No. 10, 2011, pp. 1187-1192. doi: 10.4236/jmp.2011.210148.

Conflicts of Interest

The authors declare no conflicts of interest.


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