title: Spin-flip processes and ultrafast magnetization dynamics in Co: Unifying the microscopic and macroscopic view of femtosecond magnetism.
abstract: The femtosecond magnetization dynamics of a thin cobalt film excited with ultrashort laser pulses has been studied using two complementary pump-probe techniques, namely, spin-, energy-, and time-resolved photoemission and the time-resolved magneto-optical Kerr effect. Combining the two methods, it is possible to identify the microscopic electron spin-flip mechanisms responsible for the ultrafast macroscopic magnetization dynamics of the cobalt film. In particular, we show that electron-magnon excitation does not affect the overall magnetization even though it is an efficient spin-flip channel on the sub-200 fs time scale. Instead, we find experimental evidence for the relevance of Elliott-Yafet-type spin-flip processes for the ultrafast demagnetization taking place on a time scale of 300 fs.
authors.affiliation: Physics Department, University of Kaiserslautern, Erwin-Schrödinger-Strasse 46, 67663 Kaiserslautern, Germany. cinchett@rhrk.uni-kl.de
authors.forename: M
authors.initials: M
authors.lastname: Cinchetti
authors.forename: M
authors.initials: M
authors.lastname: Sánchez Albaneda
authors.forename: D
authors.initials: D
authors.lastname: Hoffmann
authors.forename: T
authors.initials: T
authors.lastname: Roth
authors.forename: J-P
authors.initials: JP
authors.lastname: Wüstenberg
authors.forename: M
authors.initials: M
authors.lastname: Krauss
authors.forename: O
authors.initials: O
authors.lastname: Andreyev
authors.forename: H C
authors.initials: HC
authors.lastname: Schneider
authors.forename: M
authors.initials: M
authors.lastname: Bauer
authors.forename: M
authors.initials: M
authors.lastname: Aeschlimann