title: Ultrafast amorphization in Ge(10)Sb(2)Te(13) thin film induced by single femtosecond laser pulse.
abstract: We demonstrate amorphization in a Ge(10)Sb(2)Te(13) (GST) thin film through a nonthermal process by femtosecond electronic excitation. Amorphous recording marks were formed by irradiation with a single femtosecond pulse, and were confirmed to be recrystallized by laser thermal annealing. Scanning electron microscope observations revealed that amorphization occurred below the melting temperature. We performed femtosecond pump-probe measurements to investigate the amorphization dynamics of a GST thin film. We found that the reflectivity dropped abruptly within 500fs after excitation by a single pulse and that a small change in the reflectivity occurred within 5ps of this drop.
authors.affiliation: Graduate School of Science and Technology, Keio University, Hiyoshi, Kohoku,Yokohama, Kanagawa 223-8522, Japan.
authors.forename: Mitsutaka
authors.initials: M
authors.lastname: Konishi
authors.forename: Hisashi
authors.initials: H
authors.lastname: Santo
authors.forename: Yuki
authors.initials: Y
authors.lastname: Hongo
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Tajima
authors.forename: Masaharu
authors.initials: M
authors.lastname: Hosoi
authors.forename: Toshiharu
authors.initials: T
authors.lastname: Saiki