https://doi.org/10.1140/epjb/e2011-20507-1
Regular Article
Spin-switch effect in a graphene d-wave superconductor spin-valve
1
School of Physics, Anyang Normal University,
Anyang
455000, P.R.
China
2
Department of Mathematics, Henan Institute of Science and
Technology, Xinxiang
453000, P.R.
China
3
Foreign Languages Department, Henan Institute of Science and
Technology, Xinxiang
453000, P.R.
China
a
e-mail: chunxubai@yahoo.cn
Received: 24 June 2011
Received in final form: 10 September 2011
Published online: 31 October 2011
In this paper, spin-switch effect under the influence of anisotropic pairing symmetry is investigated. It is shown that the non-local conductance is sensitive to the exchange splitting, the incident energy, and the orientation of the superconducting gap. With the increase of the exchange splitting from zero to Fermi energy, the crossed Andreev reflection conductance for parallel configuration of magnetization and the elastic co-tunneling conductance for antiparallel configuration of magnetization are suppressed to a vanishing value. When the exchange splitting equates to Fermi energy, for values of the orientation of d-wave superconducting gap in the k-space very close to π / 4, magnitude of the spin-switch effect is suppressed completely. Moreover, in contrast to the single graphene-based ferromagnet/superconductor junction case, a π / 2 periodic oscillatory behavior about the barrier is observed directly in the present spin valve. The physical origination for those phenomena has also been analyzed.
© EDP Sciences, Società Italiana di Fisica and Springer-Verlag, 2011