2004/03/31 by Claudius Gros, Kay Hamacher, Wolfgang Wenzel
Physics and Astronomy · #cond-mat.str-el
paper · pdf · doi:10.1209/epl/i2004-10379-x
published as Europhysics Lett. 69, 616 (2005)
arxiv created 2004/09/17 · arxiv updated 2009/12/01
We investigate the momentum distribution function near the Mott-Hubbard transition in the one-dimensional t1-t2 Hubbard model (the zig-zag Hubbard chain), with the density-matrix renormalization-group technique. We show that for strong interactions the Mott-Hubbard transition occurs between the metallic-phase and an insulating dimerized phase with incommensurate spin excitations, suggesting a decoupling of magnetic and charge excitations not present in weak coupling. We illustrate the signatures for the Mott-Hubbard transition and the commensurate-incommensurate transition in the insulating spin-gapped state in their respective ground-state momentum distribution functions.