Kremer, Geoffroy Jaouen, Thomas Salzmann, Björn Nicolaï, L. Rumo, Maxime Nicholson, Christopher W. Hildebrand, Baptiste Dil, J. Hugo Springholz, G. Krempasky, Juraj Monney, Claude 2020 α−GeTe(111) is a noncentrosymmetric ferroelectric material for which a strong spin- orbit interaction gives rise to giant Rashba split states in the bulk and at the surface. The detailed dispersions of the surface states inside the bulk band gap remains an open question because they are located in the unoccupied part of the electronic structure, making them inaccessible to static angle-resolved photoemission spectroscopy. We show that this difficulty can be overcome via in situ potassium doping of the surface, leading to a rigid shift of 80 meV of the surface states into the occupied states. Thus, we resolve, in great detail, their dispersion and highlight their crossing at the ... point, which, in comparison with density functional theory calculations, definitively confirms the Rashba mechanism. application/pdf https://folia.unifr.ch/global/documents/309596 https://folia.unifr.ch/documents/309596/files/kremer_et_al_2020_unveiling.pdf eng info:eu-repo/semantics/altIdentifier/doi/10.1103/PhysRevResearch.2.033115 info:eu-repo/semantics/openAccess License undefined Physical Review Research. - 2020, vol. 2, no. 3, p. 033115 Ferroelectricity Rashba coupling Surface states Angle-resolved photoemission spectroscopy Density functional calculations Scanning tunneling microscopy info:eu-repo/classification/udc/53 Unveiling the complete dispersion of the giant Rashba split surface states of ferroelectric α−GeTe(111) by alkali doping http://purl.org/coar/resource_type/c_6501