title: One-dimensional orbital excitations in vanadium oxides.
abstract: The d electron orbital is a hidden but important degree of freedom controlling novel properties of transition-metal oxides. A one-dimensional orbital system is especially intriguing due to its enhanced quantum fluctuation. We present a combined experimental and theoretical study on the Raman scattering spectra in perovskite oxides NdVO(3) and LaVO(3) to prove that the quasi-one-dimensional orbital chain described by fermionic pseudospinons bears orbital excitations exchanging occupied orbital states on the neighboring sites, termed a two-orbiton in analogy with two-magnon.
authors.affiliation: Department of Applied Physics, University of Tokyo, Tokyo 113-8656, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Miyasaka
authors.forename: S
authors.initials: S
authors.lastname: Onoda
authors.forename: Y
authors.initials: Y
authors.lastname: Okimoto
authors.forename: J
authors.initials: J
authors.lastname: Fujioka
authors.forename: M
authors.initials: M
authors.lastname: Iwama
authors.forename: N
authors.initials: N
authors.lastname: Nagaosa
authors.forename: Y
authors.initials: Y
authors.lastname: Tokura