2014/05/13 by S. McKeown Walker, A. de la Torre, F. Y. Bruno +8 · 111 citations
Engineering · Materials Science · Physics and Astronomy · #Anisotropy #Atomic physics #Condensed matter physics #Electron #Electronic and Structural Properties of Oxides #Electronic structure #Fermi gas #Fermi surface #Geometry #Magnetic and transport properties of perovskites and related materials #Materials science #Molecular physics #Optics #Physics #Quantum mechanics #Semiconductor materials and devices #Surface (topology) #cond-mat.mtrl-sci #cond-mat.str-el
paper · pdf · doi:10.1103/physrevlett.113.177601
published in Physical Review Letters 113(17), 177601 (American Physical Society) · 5 pages, 4 figures
arxiv created 2014/05/13 · openalex publication_date 2014/10/20 · arxiv updated 2014/10/29 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/06
We report on the formation of a two-dimensional electron gas (2DEG) at the bare surface of (111) oriented SrTiO3. Angle resolved photoemission experiments reveal highly itinerant carriers with a sixfold symmetric Fermi surface and strongly anisotropic effective masses. The electronic structure of the 2DEG is in good agreement with self-consistent tight-binding supercell calculations that incorporate a confinement potential due to surface band bending. We further demonstrate that alternate exposure of the surface to ultraviolet light and atomic oxygen allows tuning of the carrier density and the complete suppression of the 2DEG.