Atomically resolved spectroscopic study of Sr.sub.2./sub.IrO.sub.4./sub.: Experiment and theory

0399018 - FZÚ 2014 RIV GB eng J - Článek v odborném periodiku
Li, Q. - Cao, G. - Okamoto, S. - Yi, J. - Lin, W. - Sales, B.C. - Yan, J. - Arita, R. - Kuneš, Jan - Kozhevnikov, A.V. - Eguiluz, A.G. - Imada, M. - Gai, Z. - Pan, M. - Mandrus, D.G.
Atomically resolved spectroscopic study of Sr₂IrO₄: Experiment and theory.
Scientific Reports. Roč. 3, OCT (2013), s. 1-7. ISSN 2045-2322. E-ISSN 2045-2322
Grant CEP: GA ČR GA13-25251S
Institucionální podpora: RVO:68378271
Klíčová slova: Sr₂IrO₄ * scanning tunneling microscopy * Mott insulator * Slater insulator
Kód oboru RIV: BM - Fyzika pevných látek a magnetismus
Impakt faktor: 5.078, rok: 2013
http://www.nature.com/srep/2013/131029/srep03073/full/srep03073.html

In Sr2IrO4, the interplay between spin-orbit coupling, bandwidth and on-site Coulomb repulsion stabilizes a Jeff=1/2 spin-orbital entangled insulating state at low temperatures. Whether this insulating phase is Mott- or Slater-type, has been under intense debate. We address this issue via spatially resolved imaging and spectroscopic studies of the Sr2IrO4 surface using scanning tunneling microscopy/ spectroscopy. STS results show opening of an gap (150,250 meV) below the Ne´el temperature, in qualitative agreement with our density-functional theory calculations. More importantly, the temperature dependence of the gap is consistent with our dynamical mean field theory results, both showing a continuous transition from a gapped insulating ground state to a non-gap phase as temperatures approach TN. These results indicate a significant Slater character of gap formation, thus suggesting that Sr2IrO4 is a uniquely correlated system, where Slaterand Mott-Hubbard-type behaviors coexist.
Trvalý link: http://hdl.handle.net/11104/0226412