Large spin splitting of metallic surface-state bands at adsorbate-modified gold/silicon surfaces

Abstract

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License.-- et al.Finding appropriate systems with a large spin splitting of metallic surface-state band which can be fabricated on silicon using routine technique is an essential step in combining Rashba-effect based spintronics with silicon technology. We have found that originally poor structural and electronic properties of the Au/Si(111) √3x√3 surface can be substantially improved by adsorbing small amounts of suitable species (e.g., Tl, In, Na, Cs). The resultant surfaces exhibit a highly-ordered atomic structure and spin-split metallic surface-state band with a momentum splitting of up to 0.052 Å−1 and an energy splitting of up to 190 meV at the Fermi level. The family of adsorbate-modified Au/Si(111) √3x√3 surfaces, on the one hand, is thought to be a fascinating playground for exploring spin-splitting effects in the metal monolayers on a semiconductor and, on the other hand, expands greatly the list of material systems prospective for spintronics applications.Part of this work was supported by the Russian Foundation for Basic Research (Grant Nos. 11-02-98515r, 12-02-00416, 12-02-00430 and 12-02-31745), the Ministry of Education and Science of the RF (Grant Nos. 8022, 8581, 2.8575.2013 and 2.1004.2011), NSh-774.2012.2, the Basque Country Government, Departamento de Educación, Universidades e Investigación (Grant No. IT-366-07), the Spanish Ministerio de Ciencia e Innovación (Grant No. FIS2010-19609-C02-00), German-Russian Interdisciplinary Science Center (G-RISC) funded by the German Federal Foreign Office via the German Academic Exchange Service (DAAD) and Helmholtz Zentrum Berlin fur Materialien und Energie for support within a bilateral Program ‘‘Russian-German Laboratory’’ at BESSY-II. We thank S.S. Tsirkin for help with graphical presentation of results. D.U. and A.F. acknowledge support from SPbU grant.Peer reviewe