TY  - JOUR
A1  - Bareille, C.
A1  - Fortuna, F.
A1  - Rödel, T. C.
A1  - Bertran, F.
A1  - Gabay, M.
A1  - Hijano Cubelos, O.
A1  - Taleb-Ibrahimi, A.
A1  - Le Fèvre, P.
A1  - Bibes, M.
A1  - Barthelemy, A.
A1  - Maroutian, T.
A1  - Lecoeur, P.
A1  - Rozenberg, M. J.
A1  - Santander-Syro, A. F.
T1  - Two-dimensional electron gas with six-fold symmetry at the (111) surface of KTaO3
JF  - Scientific Reports
N2  - Two-dimensional electron gases (2DEGs) at transition-metal oxide (TMO) interfaces, and boundary states in topological insulators, are being intensively investigated. The former system harbors superconductivity, large magneto-resistance, and ferromagnetism. In the latter, honeycomb-lattice geometry plus bulk spin-orbit interactions lead to topologically protected spin-polarized bands. 2DEGs in TMOs with a honeycomb-like structure could yield new states of matter, but they had not been experimentally realized, yet. We successfully created a 2DEG at the (111) surface of KTaO3, a strong insulator with large spin-orbit coupling. Its confined states form a network of weakly-dispersing electronic gutters with 6-fold symmetry, a topology novel to all known oxide-based 2DEGs. If those pertain to just one Ta-(111) bilayer, model calculations predict that it can be a topological metal. Our findings demonstrate that completely new electronic states, with symmetries not realized in the bulk, can be tailored in oxide surfaces, promising for TMO-based devices.
KW  - LAALO3/SRTIO3 interfaces
KW  - topological insulators
KW  - superconductivity
KW  - oxides
KW  - SRTIO3
Y1  - 2014
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-117703
SN  - 2045-2322
VL  - 4
ER  -