title: Excitation-photon-energy selectivity of photoconversions in halogen-bridged Pd-chain compounds: Mott insulator to metal or charge-density-wave state.
abstract: Ultrafast photoinduced transitions of a one-dimensional Mott insulator into two distinct electronic phases, metal and charge-density-wave (CDW) state, were achieved in a bromine-bridged Pd-chain compound [Pd(en)2Br](C5-Y)2H2O (en=ethylenediamine and C5-Y=dialkylsulfosuccinate), by selecting the photon energy of a femtosecond excitation pulse. For the resonant excitation of the Mott-gap transition, excitonic states are generated and converted to one-dimensional CDW domains. For the higher-energy excitation, free electron and hole carriers are produced, giving rise to a transition of the Mott insulator to a metal. Such selectivity in photoconversions by the choice of initial photoexcited states opens a new possibility for the developments of advanced optical switching and memory functions.
authors.affiliation: Department of Advanced Materials Science, University of Tokyo, Kashiwa, Chiba 277-8561, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Matsuzaki
authors.affiliation: Department of Advanced Materials Science, University of Tokyo, Kashiwa, Chiba 277-8561, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Iwata
authors.affiliation: Department of Advanced Materials Science, University of Tokyo, Kashiwa, Chiba 277-8561, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Miyamoto
authors.affiliation: Department of Advanced Materials Science, University of Tokyo, Kashiwa, Chiba 277-8561, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Terashige
authors.affiliation: Institute of Materials Structure Science, Graduate University for Advanced Studies, High Energy Accelerator Research Organization (KEK), Tsukuba 305-0801, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Iwano
authors.affiliation: Department of Chemistry, Tohoku University, Sendai, Miyagi 980-8578, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Takaishi
authors.affiliation: Department of Chemistry, Tohoku University, Sendai, Miyagi 980-8578, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Takamura
authors.affiliation: Department of Chemistry, Tohoku University, Sendai, Miyagi 980-8578, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Kumagai
authors.affiliation: Department of Chemistry, Tohoku University, Sendai, Miyagi 980-8578, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Yamashita
authors.affiliation: Division of Materials Physics, Graduate School of Engineering Science, Osaka University, Toyonaka 560-8531, Japan.
authors.forename: R
authors.initials: R
authors.lastname: Takahashi
authors.affiliation: Division of Materials Physics, Graduate School of Engineering Science, Osaka University, Toyonaka 560-8531, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Wakabayashi
authors.affiliation: Department of Advanced Materials Science, University of Tokyo, Kashiwa, Chiba 277-8561, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Okamoto