Letter abstract
Nature Physics 3, 168 - 171 (2007)
doi:10.1038/nphys538
Subject Categories: Condensed-matter physics | Materials physics
Kinks in the dispersion of strongly correlated electrons
K. Byczuk1,2, M. Kollar1, K. Held3, Y.-F. Yang3, I. A. Nekrasov4, Th. Pruschke5 and D. Vollhardt1
The properties of condensed matter are determined by single-particle and collective excitations and their mutual interactions. These quantum-mechanical excitations are characterized by an energy, E, and a momentum, 
k, which are related through their dispersion, Ek. The coupling of excitations may lead to abrupt changes (kinks) in the slope of the dispersion. Kinks thus carry important information about the internal degrees of freedom of a many-body system and their effective interaction. Here, we report a novel, purely electronic mechanism leading to kinks, which is not related to any coupling of excitations. Namely, kinks are predicted for any strongly correlated metal whose spectral function shows a three-peak structure with well-separated Hubbard subbands and a central peak, as observed, for example, in transition-metal oxides. These kinks can appear at energies as high as a few hundred millielectron volts, as found in recent spectroscopy experiments on high-temperature superconductors1, 2, 3, 4 and other transition-metal oxides5, 6, 7, 8. Our theory determines not only the position of the kinks but also the range of validity of Fermi-liquid theory.
- Theoretical Physics III, Center for Electronic Correlations and Magnetism, Institute for Physics, University of Augsburg, 86135 Augsburg, Germany
-
Institute of Theoretical Physics, Warsaw University, ul. Ho
a 69, PL-00-681 Warszawa, Poland
- Max Planck Institute for Solid State Research, Heisenbergstr. 1, 70569 Stuttgart, Germany
- Institute for Electrophysics, Russian Academy of Sciences, Ekaterinburg 620016, Russia
- Institute for Theoretical Physics, University of Göttingen, Friedrich-Hund-Platz 1, 37077 Göttingen, Germany
Correspondence to: K. Byczuk1,2 e-mail: Krzysztof.Byczuk@physik.uni-augsburg.de
Correspondence to: M. Kollar1 e-mail: Marcus.Kollar@physik.uni-augsburg.de
MORE ARTICLES LIKE THIS
These links to content published by NPG are automatically generated.
NEWS AND VIEWS
Superconductivity Are we there yet?Nature Physics News and Views (01 Mar 2007)
Superconductors The electron shattersNature Physics News and Views (01 Mar 2008)
See all 4 matches for News And ViewsRESEARCH
Is the nitric oxide system involved in genetic hypertension in Dahl rats?Kidney International Original Article
Quasiparticle dynamics in grapheneNature Physics Article (01 Jan 2007)
Small phonon contribution to the photoemission kink in the copper oxide superconductorsNature Letters to Editor (24 Apr 2008)
See all 44 matches for Research
