Dlubak, B.; Martin, M.-B.; Weatherup, R.S.; Yang, H.; Deranlot, C.; Blume, R.; Schloegl, R.; Fert, A.; Anane, A.; Hofmann, S.; Seneor, P.; Robertson, J.: Graphene-Passivated Nickel as an Oxidation-Resistant Electrode for Spintronics. ACS Nano 6 (2012), p. 10930-10934
10.1021/nn304424x

Abstract:
We report on graphene-passivated ferromagnetic electrodes (GPFE) for spin devices. GPFE are shown to act as spin-polarized oxidation resistant electrodes. The direct coating of nickel with few layer graphene through a readily scalable chemical vapor deposition (CVD) preocess allows the preservation of an unoxidized nickel surface upon air exposure. Fabrication and measurement of comp,lete reference tunneling spin valve structures demonstrate that the GPFE is maintained as a spin polarizer and also that the presence of the graphene coating leads to a specific sign reversal of the magneto-resistence. Hence, this work highlights a novel oxidation-resistant spin source which further unlocks low cost wet chemistry processes for spintronics devices.