Anisotropic spin gaps in BiAg2-Ag/Si(111)

Alberto Crepaldi , Stéphane Pons (1) , Emmanouil Frantzeskakis , Klaus Kern (2, 3) , Marco Grioni (4)

1 INSP - Institut des Nanosciences de Paris
2 Max-Planck-Institut für Festkörperforschung
3 Institut de Physique des Nanostructures
4 EPFL - Ecole Polytechnique Fédérale de Lausanne

We present a detailed analysis of the band structure of the root 3 x root 3 R 30 degrees BiAg2/Ag/Si(111) trilayer system by means of high resolution Angle Resolved Photoemission Spectroscopy (ARPES). BiAg2/Ag/Si(111) exhibits a complex spin-polarized electronic structure due to giant spin-orbit interactions. We show that a complete set of constant energy ARPES maps, supplemented by a modified nearly free electron calculation, provides a unique insight into the structure of the spin-polarized bands and spin gaps. We also show that the complex gap structure can be continuously tuned in energy by a controlled deposition of an alkali metal.

Domaines: Matière Condensée [cond-mat]

Alberto Crepaldi, Stéphane Pons, Emmanouil Frantzeskakis, Klaus Kern, Marco Grioni. Anisotropic spin gaps in BiAg2-Ag/Si(111). Physical Review B: Condensed Matter and Materials Physics (1998-2015), 2012, 85 (7), pp.075411. ⟨10.1103/PhysRevB.85.075411⟩. ⟨hal-01233583⟩