title: Hole dynamics in spin and orbital ordered vanadium perovskites.
abstract: A theory of doped perovskite vanadates with spin and orbital orders is presented. Mobile holes are strongly renormalized by spin excitations (magnons) in the spin G-type and orbital C-type (SG-OC) order, and orbital excitations (orbitons) in the spin C-type and orbital G-type (SC-OG) one. Hole dynamics in a staggered t(2g) orbital array is distinguished from that in the antiferromagnetic order and the e(g) orbital one. The fragile character of the (SG-OC) order in Y1-xCaxVO3 is attributed to the orbiton softening induced by a reduction of the spin order parameter.
authors.affiliation: Department of Physics, Tohoku University, Sendai 980-8578, Japan.
authors.forename: Sumio
authors.initials: S
authors.lastname: Ishihara