Illuminating the surface spin texture of the giant-Rashba quantum-well system Bi/Ag(111) by circularly polarized photoemission.
We have mapped out the spin texture of a Bi/Ag surface alloy prepared on a thin Ag film by circularly polarized angle-resolved photoemission spectroscopy. A term proportional to ∇·A in the interaction Hamiltonian gives rise to strong surface photoexcitation, which interferes with a Rashba contribution to yield a pronounced circular dichroic effect in Bi/Ag. The dipole transition, often taken to be the only important photoexcitation mechanism, is actually negligible. A parameter-free calculation yields a dichroic pattern in excellent agreement with experiment.
Department of Physics, University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, Illinois 61801-3080, USA.
Guang
G
Bian
Longxiang
L
Zhang
Yang
Y
Liu
T
T
Miller
T-C
TC
Chiang