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arXiv · 1203.0520

Three-Dimensional Spin Rotations at the Fermi Surface of a Strongly Spin-Orbit Coupled Surface System

Philipp Hoepfner·Joerg Schaefer·Andrzej Fleszar·Jan Hugo Dil·Bartosz Slomski·Fabian Meier·Christoph Loho·Christian Blumenstein·Luc Patthey·Werner Hanke·Ralph Claessen
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Abstract

The spin texture of the metallic two-dimensional electron system (root3 x root3)-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 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 towards 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.

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Philipp Hoepfner, Joerg Schaefer, Andrzej Fleszar, Jan Hugo Dil, Bartosz Slomski, Fabian Meier, Christoph Loho, Christian Blumenstein, Luc Patthey, Werner Hanke, Ralph Claessen. 2012-03-02. Three-Dimensional Spin Rotations at the Fermi Surface of a Strongly Spin-Orbit Coupled Surface System. https://doi.org/10.1103/physrevlett.108.186801

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