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Exchange bias in ferromagnetic bilayers with orthogonal anisotropies: the case of GaMnAsP/GaMnAs combination.

ABSTRACT: We report the observation of exchange bias in a ferromagnetic Ga_0.94Mn_0.06As_0.77P_0.23/ Ga_0.94Mn_0.06As bilayer, in which the easy axis in one layer is oriented out-of-plane, and in the other in-plane. Magnetization reversal in this system is explored using planar Hall effect (PHE) measurements under various initial conditions and with various field-cooling orientations. Our results show that the two magnetic layers are ferromagnetically exchange-coupled, and that such coupling results in pronounced exchange-bias-like shifts of magnetic hysteresis loops during reversal of in-plane magnetization. The presence of exchange bias in this system can be understood on the basis of magnetic closure domains formed in the layer with the out-of-plane easy axis.

SUBMITTER: Choi S

PROVIDER: S-EPMC6736936 | biostudies-literature |

REPOSITORIES: biostudies-literature

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