Title :
Enhanced Exchange Bias of Spin Valves Fabricated on Fullerene-Based Seed Layers
Author :
Wheeler, M. ; Hickey, B.J. ; Céspedes, O.
Author_Institution :
Condensed Matter Dept., Univ. of Leeds, Leeds, UK
Abstract :
The magnetic properties of exchange biased systems deposited on top of fullerene-based materials have been studied. An enhanced exchange bias field has been observed for Si/SiO2/C60/Co/Cu/Co/IrMn/Ta and Si/SiO2 /FeC60 /Co/Cu/Co/IrMn/Ta in comparison to a typical structure of Si/SiO2/Ta/Co/Cu/Co/IrMn/Ta. Here the magnetic properties of the devices are changed significantly with an organic underlayer or seed layer. The magnetic ordering is well maintained, and C60 seeding results in an exchange bias of (19.5 ±0.5) mT, some 7 mT higher than that of Ta seeded spin valves (12.5 ±0.5 mT). A combination of MOKE (magneto-optical Kerr effect), X-ray diffraction and Raman spectroscopy have been used to characterize the materials and further understand the interactions between the Co and fullerene-based materials.
Keywords :
Kerr magneto-optical effect; Raman spectra; X-ray diffraction; cobalt; copper; exchange interactions (electron); fullerenes; iridium alloys; iron compounds; manganese alloys; organic compounds; silicon; silicon compounds; spin valves; tantalum; MOKE; Raman spectroscopy; Si-SiO2-C60-Co-Cu-Co-IrMn-Ta; Si-SiO2-FeC60-Co-Cu-Co-IrMn-Ta; X-ray diffraction; enhanced exchange bias; fullerene based seed layer; magnetic ordering; magnetooptical Kerr effect; organic underlayer; spin valve; Coercive force; Magnetic properties; Magnetic tunneling; Magnetoelectronics; Silicon; Spin valves; C $_{60}$; exchange bias; magnetoresistance; organic spintronics;
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2012.2198200
