Exchange Bias in CrO₂/Cr₂O₃ Bilayer Thin Films

Abstract:

We have investigated the exchange bias in CVD grown epitaxial CrO2/Cr2O3 bilayer thin films using hysteresis loops and resonant RF transverse susceptibility. M-H loops indicated an enhanced coercivity without appreciable loop shift and the transverse susceptibility in CrO2/Cr2O3 bilayers revealed features associated with both the ferromagnetic and antiferromagnetic phases. In addition, TS yielded large anisotropy constant (Keff) values depending on the fraction of Cr2O3 present. The large anisotropy fields observed cannot be accounted for by the variable thickness of CrO2 alone and are indicative of possible exchange coupling between CrO2 and Cr2O3 phases that significantly affects the effective magnetic anisotropy.

• Periodical: Advances in Science and Technology (Volume 45)
• Pages: 2528-2533
• DOI: https://doi.org/10.4028/www.scientific.net/AST.45.2528
• Online since: October 2006
• Authors: S. Srinath, N.A. Frey, H. Srikanth, G.X. Miao, A. Gupta
• Keywords: Anisotropy, Exchange Bias, Oxide Thin Films, Transverse Susceptibility

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