Spin-dependent barrier effects on the transport properties of graphene-based normal metal/ferromagnetic barrier/d-wave superconductor junction

• Published in: Journal of magnetism and magnetic materials 2014-08, Vol.362, p.36-41
• Main Authors: Hajati, Y., Heidari, A., Shoushtari, M.Z., Rashedi, G.
• Format: Article
• Language: English
• Subjects: Barriers; Charge; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Conductance; Electronic transport in condensed matter; Exact sciences and technology; Ferromagnetic barrier; Ferromagnetism; Filtering; Filtration; Graphene; Multilayers, superlattices , heterostructures; Physics; Rotation angle; Spin filtering application; Spin polarized transport; Superconducting films and low-dimensional structures; Superconductivity; Superconductor junctions; Transport properties
• ISSN: 0304-8853
• DOI: 10.1016/j.jmmm.2014.03.018

Using the extended Blonder–Tinkham–Klapwijk formalism, the spin-dependent transport properties in a graphene-based normal metal/ferromagnetic barrier/d-wave superconductor (NFBd-wave) junction have been studied theoretically. Here, we have mainly studied the influences of spin-dependent barrier and rotation angle of d-wave superconducting order parameter (α) on the charge and spin conductance. It is found that the rotation angle has a strong effect on the amplitude and phase of the charge conductance oscillations. As a remarkable result, we obtained that because of the spin-dependent barrier (FB), the rotation angle cannot suppress the zero-bias charge conductance and for the maximum rotation angle α=π/4, the charge conductance shows oscillatory behavior which is different from similar non-spin-dependent barrier junctions. We have also shown that the spin filtering application of this junction is drastically changed by the rotation angle α. As α increases, the spin filtering application enhances, being strongest for α=π/4. At last, we propose an experimental setup to detect our predicted effects. •Rotation angle has a strong effect on the amplitude of the charge conductance.•The zero-bias charge conductance cannot be suppressed by the rotation angle.•The spin filtering application of the junction can be tuned by the rotation angle.•The peak of the charge conductance is replaced by lower eV by increasing α.•At the maximum rotation angle the charge conductance shows oscillatory behavior.