Designing the Rashba spin texture by adsorption of inorganic molecules

ORAL

Abstract

We present an approach in which we show that the spin texture of a surface Rashba system can be adjusted by the adsorption of molecules. By selecting physisorbed and chemisorbed inorganic molecules on the BiAg$_2$/Ag(111) surface alloy [1] we demonstrate from \emph{ab initio} that both the spin-orbit splitting and the spin direction of Rashba-split surface states can be controlled selectively. The physisorption of NH$_3$ gives rise to a slightly enhanced outward buckling of the surface Bi which enlarges the magnitude of the Rashba splitting. On the contrary, the weak chemisorption of BH$_3$ defines a strong inward relaxation of the surface Bi. This causes the occupied Rashba split state to shift into Ag bulk states. In addition a new Rashba splitting is created in an unoccupied state upon BH$_3$ adsorption. Most importantly, in contrast to the clean surface [1] in case of the BH$_3$-BiAg$_2$/Ag(111) system the out-of-plane spin polarization is significantly larger than the in-plane one. \newline [1] C. R. Ast, \emph{et al.}, PRL \textbf{98}, 186807 (2007).

*We gratefully acknowledge financial support from the Volkswagen-Stiftung through the ”Optically Controlled Spin Logic” project and SFB 1238 (Project C01).

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Authors

  • Rico Friedrich

    • Peter Gr\"unberg Institut (PGI-1) and Institute for Advanced Simulation (IAS-1), Forschungszentrum J\"ulich and JARA

  • Vasile Caciuc

    • Forschungszentrum J\"{u}lich, Germany
    • Peter Gr\"unberg Institut (PGI-1) and Institute for Advanced Simulation (IAS-1), Forschungszentrum J\"ulich and JARA, D-52425 J\"ulich, Germany
    • Peter Gr\"unberg Institut (PGI-1) and Institute for Advanced Simulation (IAS-1), Forschungszentrum J\"ulich and JARA

  • Gustav Bihlmayer

    • Forschungszentrum Juelich
    • Peter Gr\"unberg Institut (PGI-1) and Institute for Advanced Simulation (IAS-1), Forschungszentrum J\"ulich and JARA

  • Nicolae Atodiresei

    • Forschungszentrum J\"{u}lich, Germany
    • Peter Gr\"unberg Institut (PGI-1) and Institute for Advanced Simulation (IAS-1), Forschungszentrum J\"ulich and JARA, D-52425 J\"ulich, Germany
    • Peter Gr\"unberg Institut (PGI-1) and Institute for Advanced Simulation (IAS-1), Forschungszentrum J\"ulich and JARA

  • Stefan Bl\"ugel

    • Forschungszentrum J\"{u}lich, Germany
    • Forschungszentrum Juelich
    • Peter Gr\"unberg Institut (PGI-1) and Institute for Advanced Simulation (IAS-1), Forschungszentrum J\"ulich and JARA, D-52425 J\"ulich, Germany
    • Peter Gruenberg Institute and Institute for Advanced Simulation, Forschungszentrum Juelich and JARA, 52425 Juelich, Germany
    • Peter Gr\"unberg Institut (PGI-1) and Institute for Advanced Simulation (IAS-1), Forschungszentrum J\"ulich and JARA
    • Peter Gr\"unberg Institut and Institute for Advanced Simulation, Forschungszentrum J\"ulich and JARA, 52425 J\"ulich, Germany