title: Photoinduced Barkhausen effect in the ferromagnetic semiconductor (Ga,Mn)As.
abstract: Magnetization of ferromagnetic materials commonly occurs via random jumps of domain walls between pinning sites, a phenomenon known as the Barkhausen effect. Using strongly focused light pulses of appropriate power and duration we demonstrate the ability to selectively activate single jumps in the domain wall propagation in (Ga,Mn)As, manifesting itself as a discrete photoinduced domain wall creep as a function of illumination time. The propagation velocity can be increased over 7 orders of magnitude varying the illumination power density and the magnetic field.
authors.affiliation: Physikalisches Institut, EP3, Universität Würzburg, 97074 Würzburg, Germany. astakhov@physik.uni-wuerzburg.de
authors.forename: G V
authors.initials: GV
authors.lastname: Astakhov
authors.forename: J
authors.initials: J
authors.lastname: Schwittek
authors.forename: G M
authors.initials: GM
authors.lastname: Schott
authors.forename: C
authors.initials: C
authors.lastname: Gould
authors.forename: W
authors.initials: W
authors.lastname: Ossau
authors.forename: K
authors.initials: K
authors.lastname: Brunner
authors.forename: L W
authors.initials: LW
authors.lastname: Molenkamp