McKeown Walker, S.; Riccò, S.; Bruno, F. Y.; de la Torre, A.; Tamai, A.; Golias, E.; Varykhalov, A.; Marchenko, D.; Hoesch, M.; Bahramy, M. S.; King, P. D. C.; Sánchez-Barriga, J.; Baumberger, F.: Absence of giant spin splitting in the two-dimensional electron liquid at the surface of SrTiO3 (001). Physical Review B 93 (2016), p. 245143
10.1103/PhysRevB.93.245143

Abstract:
We reinvestigate the putative giant spin splitting at the surface of SrTiO3 reported by Santander–Syro et al. [Nat. Mater. 13, 1085 (2014)]. Our spin- and angle-resolved photoemission experiments on fractured (001) oriented surfaces supporting a two-dimensional electron liquid with high carrier density show no detectable spin polarization in the photocurrent. We demonstrate that this result excludes a giant spin splitting while it is consistent with the unconventional Rashba-like splitting seen in band structure calculations that reproduce the experimentally observed ladder of quantum confined subbands.