Volume 85, Number 2, January 2009
Article Number 27011
Number of page(s) 6
Section Condensed Matter: Electronic Structure, Electrical, Magnetic and Optical Properties
Published online 30 January 2009
EPL, 85 (2009) 27011
DOI: 10.1209/0295-5075/85/27011

Dimensional crossover in Sr2RuO4 within a slave-boson mean-field theory

M. H. Fischer and M. Sigrist

Institute for Theoretical Physics, ETH Zürich - CH-8093 Zürich

received 28 August 2008; accepted in final form 5 January 2009; published January 2009
published online 30 January 2009

Motivated by the anomalous temperature dependence of the c-axis resistivity of Sr2RuO4, the dimensional crossover from a network of perpendicular one-dimensional chains to a two-dimensional system due to a weak hybridization between the perpendicular chains is studied. The corresponding two-orbital Hubbard model is treated within a slave-boson mean-field theory (SBMFT) to take correlation effects into account such as the spin-charge separation on the one-dimensional chains. Using an RPA-like formulation for the Green's function of collective spinon-holon excitations the emergence of quasiparticles at low-temperatures is examined. The results are used to discuss the evolution of the spectral density and the c-axis transport within a tunneling approach. For the latter a regime change between low- and high-temperature regime is found in qualitative accordance with experimental data.

71.27.+a - Strongly correlated electron systems; heavy fermions.
71.10.Pm - Fermions in reduced dimensions (anyons, composite fermions, Luttinger liquid, etc.).
71.10.Fd - Lattice fermion models (Hubbard model, etc.).

© EPLA 2009