Hoepfner, P.Schaefer, J.Fleszar, A.Dil, J. H.Slomski, B.Meier, F.Loho, C.Blumenstein, C.Patthey, L.Hanke, W.Claessen, R.2015-06-232015-06-232015-06-23201210.1103/PhysRevLett.108.186801https://infoscience.epfl.ch/handle/20.500.14299/115358WOS:000303384100009The spin texture of the metallic two-dimensional electron system (root 3 x root 3)-Au/Ge(111) is revealed by fully three-dimensional spin-resolved photoemission, as well as by density functional calculations. The large hexagonal Fermi surface, generated by the Au atoms, shows a significant splitting due to spin-orbit interactions. The planar components of the spin exhibit a helical character, accompanied by a strong out-of-plane spin component with alternating signs along the six Fermi surface sections. Moreover, in-plane spin rotations toward a radial direction are observed close to the hexagon corners. Such a threefold-symmetric spin pattern is not described by the conventional Rashba model. Instead, it reveals an interplay with Dresselhaus-like spin-orbit effects as a result of the crystalline anisotropies.text::journal::journal article::research article