We investigate transmission properties of electrons at the interfaces of cobalt-diamond hybrid systems. To this end, we employ a Green's function method based on spin-polarized density-functional theory calculations using a Gaussian orbital representation of the wave functions. The considered open systems are magnetic tunnel junctions consisting of semi-infinite hcp cobalt leads and $n$ layers of carbon atoms stacked in (111) direction. These systems are characterized by a very small lattice mismatch of their constituents. We have identified three types of states that give rise to an almost complete transmission. The transmission for minority electrons is considerably suppressed at the Fermi level in most parts of the interface Brillouin zone.

• Received 28 August 2013
• Revised 11 November 2013

DOI:https://doi.org/10.1103/PhysRevB.89.125302