Berlin 2018 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

O: Fachverband Oberflächenphysik

O 3: Ultrafast Electron and spin dynamics at interfaces I

O 3.1: Vortrag

Montag, 12. März 2018, 10:30–10:45, MA 005

Mechanism of spin-dependent electron transfer on ferromagnetic interfaces: theory and application — •Simiam Ghan, Harald Oberhofer, and Karsten Reuter — Technical University of Munich, Garching, Germany.

Self-assembled monolayers of organic molecules (SAMs) on surfaces show great promise in the emerging field of molecular electronics due to tunable charge transport properties, long-range 2-dimensional order and ease of manufacture. Growth of SAMs on ferromagnetic surfaces offers the additional possibility of spin-dependent transport, making these systems relevant to molecular spintronics in e.g. spin-valves and magnetic tunneling junctions. In order to establish design principles for such applications, a thorough understanding of charge transport mechanisms over SAM-metal interfaces is of great importance.

As an initial benchmark in this direction, we report calculations of spin-dependent electron transport in model systems of Argon monolayers on ferromagnetic Fe(110), Co(0001) and Ni(111) substrates. Spin-polarized charge transfer rates are calculated from the Fermi Golden Rule and explicit time propagation using first-principles parametrized model Hamiltonians. Results are compared to ultrafast core-hole-clock spectroscopy measurements, which found faster transport for minority electrons [1]. After benchmarking the protocol on Ar-metal systems we apply it to thiol-based model SAMs with an aim towards predicting tunable spin-transport behavior.

[1] F. Blobner et al., Phys. Rev. Lett. 112, 086801 (2014).