title: Optical manipulation of coherent phonons in superconducting YBa2Cu3O7-delta thin films.
abstract: The coherent phonons of YBa2Cu3O7-delta are believed to be strongly coupled to its superconductivity. Controlling the phonons below its transition temperature, therefore, may serve as a promising scheme of the control of superconductivity. Here we demonstrate optical manipulation of the Ba-O and Cu-O vibrations in a thin-film YBa2Cu3O7-delta below its transition temperature using a pair of femtosecond laser pulses. The interpulse delay is tuned to integral and half-integral multiples of the oscillation period of a specific phonon mode (Ba-O or Cu-O vibration) to enhance and suppress its amplitude, respectively.
authors.affiliation: Institute for Molecular Science, National Institutes of Natural Sciences, Okazaki, 444-8585, Japan.
authors.forename: Yasuaki
authors.initials: Y
authors.lastname: Okano
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Katsuki
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Nakagawa
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Takahashi
authors.forename: Kazutaka G
authors.initials: KG
authors.lastname: Nakamura
authors.forename: Kenji
authors.initials: K
authors.lastname: Ohmori