title: Divergent precursors of the Mott-Hubbard transition at the two-particle level.
abstract: Identifying the fingerprints of the Mott-Hubbard metal-insulator transition may be quite elusive in correlated metallic systems if the analysis is limited to the single particle level. However, our dynamical mean-field calculations demonstrate that the situation changes completely if the frequency dependence of the two-particle vertex functions is considered: The first nonperturbative precursors of the Mott physics are unambiguously identified well inside the metallic regime by the divergence of the local Bethe-Salpeter equation in the charge channel. In the low-temperature limit this occurs for interaction values where incoherent high-energy features emerge in the spectral function, while at high temperatures it is traceable up to the atomic limit.
authors.affiliation: Institute of Solid State Physics, Vienna University of Technology, 1040 Vienna, Austria.
authors.forename: T
authors.initials: T
authors.lastname: Schäfer
authors.affiliation: Institute of Solid State Physics, Vienna University of Technology, 1040 Vienna, Austria.
authors.forename: G
authors.initials: G
authors.lastname: Rohringer
authors.affiliation: Max Planck Institute for Solid State Research, D-70569 Stuttgart, Germany.
authors.forename: O
authors.initials: O
authors.lastname: Gunnarsson
authors.affiliation: Dipartimento di Scienze Fisiche e Chimiche, Università dell'Aquila, and Istituto dei Sistemi Complessi, CNR, Via Vetoio I-67010 Coppito-L'Aquila, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Ciuchi
authors.affiliation: Institut für Theoretische Physik und Astrophysik, Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany.
authors.forename: G
authors.initials: G
authors.lastname: Sangiovanni
authors.affiliation: Institute of Solid State Physics, Vienna University of Technology, 1040 Vienna, Austria.
authors.forename: A
authors.initials: A
authors.lastname: Toschi