Article

Unconventional Fermi surface spin textures in the Bi_ {x} Pb_ {1− x}/Ag (111) surface alloy

Physical review. B, Condensed matter (Impact Factor: 3.66). 01/2009; 79(24). DOI: 10.1103/PhysRevB.79.241408
Source: arXiv

ABSTRACT The Fermi and Rashba energies of surface states in the BixPb1−x/Ag(111) alloy can be tuned simultaneously by changing the composition parameter x. We report on unconventional Fermi surface spin textures observed by spin and angle-resolved photoemission spectroscopy that are correlated with a topological transition of the Fermi surface occurring at x=0.5. We show that the surface states remain fully spin polarized upon alloying and that the spin-polarization vectors are approximately tangential to the constant energy contours. We discuss the implications of the topological transition for the transport of spin.

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