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Enhanced anisotropy and study of magnetization reversal in Co/C60 bilayer thin film

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 نشر من قبل Subhankar Bedanta
 تاريخ النشر 2019
  مجال البحث فيزياء
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The interface between organic semiconductor [OSC]/ferromagnetic [FM] material can exhibit ferromagnetism due to their orbital hybridization. Charge/spin transfer may occur from FM to OSC layer leading to the formation of `spinterface i.e. the interface exhibiting a finite magnetic moment. In this work, the magnetic properties of Co/C$_{60}$ bilayer thin film have been studied to probe the interface between Co and C$_{60}$ layer. Polarized neutron reflectivity [PNR] measurement indicates that the thickness and moment of the spinterface are $sim$ 2 $pm$ 0.18 nm and 0.8 $pm$ 0.2 $mu_B$/cage, respectively. The comparison of the magnetization reversal between the Co/C$_{60}$ bilayer and the parent single layer Co thin film reveals that spinterface modifies the domain microstructure. Further, the anisotropy of the bilayer system shows a significant enhancement ($sim$ two times) in comparison to its single layer counterpart which is probably due to an additional interfacial anisotropy arising from the orbital hybridization at the Co/C$_{60}$ interface.



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