title: Direct spectroscopic evidence of spin-dependent hybridization between Rashba-split surface states and quantum-well states.
abstract: The electronic structure of ultrathin Ag(111) films covered with a square root(3) x square root(3)-Bi/Ag ordered alloy was investigated by means of spin- and angle-resolved photoemission spectroscopy. Surface-state (SS) bands, spin split by the Rashba interaction, selectively couple to the quantum-well state (QWS) bands, originally spin degenerate, in the metal film. Gaps are found to open between QWS and SS with parallel spins, while free-electron-like QWS dispersions are observed for antiparallel spin configurations. The present results demonstrate that in a nonmagnetic metal film the spin degeneracy of the valence levels can be lifted by hybridization with Rashba-type SS bands.
authors.affiliation: Institute for Solid State Physics, The University of Tokyo, 5-1-5 Kashiwanoha, Chiba 277-8581, Japan.
authors.forename: Ke
authors.initials: K
authors.lastname: He
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Takeichi
authors.forename: Manami
authors.initials: M
authors.lastname: Ogawa
authors.forename: Taichi
authors.initials: T
authors.lastname: Okuda
authors.forename: P
authors.initials: P
authors.lastname: Moras
authors.forename: D
authors.initials: D
authors.lastname: Topwal
authors.forename: Ayumi
authors.initials: A
authors.lastname: Harasawa
authors.forename: Toru
authors.initials: T
authors.lastname: Hirahara
authors.forename: C
authors.initials: C
authors.lastname: Carbone
authors.forename: Akito
authors.initials: A
authors.lastname: Kakizaki
authors.forename: Iwao
authors.initials: I
authors.lastname: Matsuda