Crossed Andreev reflection in graphene-based ferromagnet-superconductor structures
Department of Physics, Beijing Normal University, 100875, Beijing, P.R. China
Corresponding author: a firstname.lastname@example.org
Revised: 7 September 2009
Published online: 22 October 2009
We report a theoretical investigation of the spin-polarized transport of relativistic electrons through a three-terminal graphene-based superconductor bipolar transistor with ferromagnetic leads. It is found that the magnetoresistance in such a system can be improved largely in comparison with that in the corresponding two-terminal structure due to the existence of the special crossed Andreev reflection, which is quite different from that in the conventional three-terminal ferromagnet-superconductor devices. The physical origination for such a phenomenon has also been analyzed. We also find that the non-local conductivity can not only exhibit different feature for parallel and antiparallel alignment, it is also easily tuned by the external magnetic field and the bias voltage.
PACS: 74.45.+c – Proximity effects; Andreev effect; SN and SNS junctions / 74.78.Na – Mesoscopic and nanoscale systems / 72.25.Mk – Spin transport through interfaces / 74.50.+r – Tunneling phenomena; point contacts, weak links, Josephson effects
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2009