A novel transition from the negative exchange bias (NEB) to the positive exchange bias (PEB), due to coexistent and competitive ferromagnetic and antiferromagnetic coupling in a molecular-beam-expitaxy-grown CrSe/Fe/GaAs(111)B structure, is described. The source of the unusual PEB effect was found to originate from the interface at the hetero-junction of Fe/GaAs(111)B while the NEB effect resulted from the CrSe/Fe bilayer structure. Phenomenological models are presented to explain the mechanism of the PEB effect and the varying asymmetry of the magnetic hysteresis of this structure as a function of the measured temperature.
ASJC Scopus subject areas
- Physics and Astronomy(all)