Unusual quasiparticle renormalizations from angle resolved photoemission on USb2
2009 (English)In: Philosophical Magazine, ISSN 1478-6435, E-ISSN 1478-6443, Vol. 89, no 22-24, 1893-1911 p.Article in journal (Refereed) Published
Angle-resolved photoemission experiments have been performed on USb2, and very narrow quasiparticle peaks have been observed in a band, which local spin-density approximation (LSDA) predicts to osculate the Fermi energy. The observed band is found to be depressed by 17 meV below the Fermi energy. Furthermore, the inferred quasiparticle dispersion relation for this band exhibits a kink at an energy of about 23 meV below the Fermi energy. The kink is not found in LSDA calculations and, therefore, is attributable to a change in the quasiparticle mass renormalization by a factor of approximately 2. The existence of a kink in the quasiparticle dispersion relation of a band that does not cross the Fermi energy is unprecedented. The kink in the quasiparticle dispersion relation is attributed to the effect of the interband self-energy, involving transitions from the osculating band into a band that does cross the Fermi energy.
Place, publisher, year, edition, pages
2009. Vol. 89, no 22-24, 1893-1911 p.
quasiparticles, mass enhancements, electron-phonon interaction, angle resolved photoemission, USb2
IdentifiersURN: urn:nbn:se:uu:diva-128325DOI: 10.1080/14786430802629501ISI: 000268606800014OAI: oai:DiVA.org:uu-128325DiVA: diva2:331268