Angular dependence of exchange bias and coercivity in polycrystalline CoFe/MnIr bilayers

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Abstract

We have investigated the angular dependence of exchange bias (Hex) and coercivity (Hc) in polycrystalline CoFe (100 nm)/MnIr(x) bilayers with x=0, 2, 4, 10 and 20 nm. The angular dependence of Hex and Hc show the abrupt kinks at critical angle (θc) in the samples of Hc>Hex. The profiles of angular dependent Hex is changed at critical antiferromagnetic layer thickness (tAFc) and shows inverse proportional behavior with field angle from 90°−θc to 90°+θc. These complex angular dependence of Hex and Hc with antiferromagnetic layer thickness can be well explained by using the Stoner–Wohlfarth (S–W) model.

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Acknowledgements

This work was supported by the KOSEF through ReCAMM in Chungnam National University.

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