title: Direct observation of the critical relaxation of polarization clusters in BaTiO3 using a pulsed x-ray laser technique.
abstract: We have developed a new method to investigate the relaxation time of the dipole moment in polarization clusters in BaTiO3. Time correlation of speckle intensities was measured by the use of a double pulsed soft x-ray laser. The evolution of the relaxation time of the dipole moment near the Curie temperature (T(C)) was investigated. The maximum relaxation time (approximately 90 ps) is shown to appear at a temperature of 4.5 K above the T(C), being coincident with the one where the maximum polarization takes place. This method is widely applicable to any other critical decay processes at phase transitions.
authors.affiliation: Department of Physics, Tokyo Gakugei University, Koganei, Tokyo 184-8501, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Namikawa
authors.forename: M
authors.initials: M
authors.lastname: Kishimoto
authors.forename: K
authors.initials: K
authors.lastname: Nasu
authors.forename: E
authors.initials: E
authors.lastname: Matsushita
authors.forename: R Z
authors.initials: RZ
authors.lastname: Tai
authors.forename: K
authors.initials: K
authors.lastname: Sukegawa
authors.forename: H
authors.initials: H
authors.lastname: Yamatani
authors.forename: H
authors.initials: H
authors.lastname: Hasegawa
authors.forename: M
authors.initials: M
authors.lastname: Nishikino
authors.forename: M
authors.initials: M
authors.lastname: Tanaka
authors.forename: K
authors.initials: K
authors.lastname: Nagashima