title: Separation of orbital contributions to the optical conductivity of BaVS(3).
abstract: The correlation-driven metal-insulator transition (MIT) of BaVS(3) was studied by polarized infrared spectroscopy. In the metallic state two types of electrons coexist at the Fermi energy: the quasi-1D metallic transport of A(1g) electrons is superimposed on the isotropic hopping conduction of localized E(g) electrons. The "bad-metal" character and the weak anisotropy are the consequences of the large effective mass m(eff) approximately 7 m(e) and scattering rate Gamma > or = 160 meV of the quasiparticles in the A(1g) band. There is a pseudogap above T(MI) = 69 K, and in the insulating phase the gap follows the BCS-like temperature dependence of the structural order parameter with Delta(ch) approximately 42 meV in the ground state. The MIT is described in terms of a weakly coupled two-band model.
authors.affiliation: Electron Transport Research Group of the Hungarian Academy of Science and Department of Physics, Budapest University of Technology and Economics, 1111 Budapest, Hungary.
authors.forename: I
authors.initials: I
authors.lastname: Kézsmárki
authors.forename: G
authors.initials: G
authors.lastname: Mihály
authors.forename: R
authors.initials: R
authors.lastname: Gaál
authors.forename: N
authors.initials: N
authors.lastname: Barisić
authors.forename: A
authors.initials: A
authors.lastname: Akrap
authors.forename: H
authors.initials: H
authors.lastname: Berger
authors.forename: L
authors.initials: L
authors.lastname: Forró
authors.forename: C C
authors.initials: CC
authors.lastname: Homes
authors.forename: L
authors.initials: L
authors.lastname: Mihály