title: Glass transition in the polaron dynamics of colossal magnetoresistive manganites.
abstract: Neutron scattering measurements on a bilayer manganite near optimal doping show that the short-range polaron correlations are completely dynamic at high T, but then freeze upon cooling to a temperature T(*) approximately equal 310 K. This glass transition suggests that the paramagnetic/insulating state arises from an inherent orbital frustration that inhibits the formation of a long-range orbital- and charge-ordered state. Upon further cooling into the ferromagnetic-metallic state (T(C) = 114 K), where the polarons melt, the diffuse scattering quickly develops into a propagating, transverse optic phonon.
authors.affiliation: Materials Science Division, Argonne National Laboratory, Argonne, Illinois, 60439, USA.
authors.forename: D N
authors.initials: DN
authors.lastname: Argyriou
authors.forename: J W
authors.initials: JW
authors.lastname: Lynn
authors.forename: R
authors.initials: R
authors.lastname: Osborn
authors.forename: B
authors.initials: B
authors.lastname: Campbell
authors.forename: J F
authors.initials: JF
authors.lastname: Mitchell
authors.forename: U
authors.initials: U
authors.lastname: Ruett
authors.forename: H N
authors.initials: HN
authors.lastname: Bordallo
authors.forename: A
authors.initials: A
authors.lastname: Wildes
authors.forename: C D
authors.initials: CD
authors.lastname: Ling