Influence of atomic roughness at the uncompensated Fe/CoO(111) interface on the exchange-bias effect

Article

关键词: ANTIFERROMAGNETIC THICKNESS DEPENDENCE;    TEMPERATURE-DEPENDENCE;    BLOCKING TEMPERATURE;    ANISOTROPY;    MAGNETIZATION;    ENHANCEMENT;    FE;    NI;   

DOI  :  10.1103/PhysRevB.101.014425

来源: SCIE

【 摘 要 】

The effect of interface roughness of ferromagnetic and antiferromagnetic layers on exchange bias is still not well understood. In this report we have investigated the effect of surface roughness in (111)-oriented antiferromagnetic CoO films on exchange bias with ferromagnetic Fe grown on top. The surface roughness is controlled at the atomic scale, over a range below similar to 0.35 nm, by varying layer thickness of the CoO films. It is observed that both exchange-bias field (H-E) and coercivity (H-C) extensively depend on the atomic scale roughness of the CoO (111) at the interface with Fe film. An opposite dependence of H-E and H-C on interface roughness was found, which was ascribed to partially compensated spin states induced by the atomic roughness at the fully uncompensated CoO (111) surfaces and was corroborated using Monte Carlo simulations. Moreover, the onset temperature for H-C is found to be up to similar to 80 K below the blocking temperature (T-B) and the temperature dependence of H-C follows the power law with a critical exponent equal to one, which indicates that, in this system, H-C is more of an interface-related property than H-E.

【 授权许可】

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