title: Photoemission of a doped Mott insulator: spectral weight transfer and a qualitative Mott-Hubbard description.
abstract: The spectral weight evolution of the low-dimensional Mott insulator TiOCl upon alkali-metal dosing has been studied by photoelectron spectroscopy. We observe a spectral weight transfer between the lower Hubbard band and an additional peak upon electron doping, in line with quantitative expectations in the atomic limit for changing the number of singly and doubly occupied sites. This observation is an unconditional hallmark of correlated bands and has not been reported before. In contrast, the absence of a metallic quasiparticle peak can be traced back to a simple one-particle effect.
authors.affiliation: Experimentelle Physik 4, Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Sing
authors.forename: S
authors.initials: S
authors.lastname: Glawion
authors.forename: M
authors.initials: M
authors.lastname: Schlachter
authors.forename: M R
authors.initials: MR
authors.lastname: Scholz
authors.forename: K
authors.initials: K
authors.lastname: Goss
authors.forename: J
authors.initials: J
authors.lastname: Heidler
authors.forename: G
authors.initials: G
authors.lastname: Berner
authors.forename: R
authors.initials: R
authors.lastname: Claessen