title: Nonthermal photocoercivity effect in a low-doped (Ga,Mn)As ferromagnetic semiconductor.
abstract: We report a photoinduced change of the coercive field, i.e., a photocoercivity effect (PCE), under very low intensity illumination of a low-doped (Ga,Mn)As ferromagnetic semiconductor. We find a strong correlation between the PCE and the sample resistivity. Spatially resolved dynamics of the magnetization reversal rule out any role of thermal heating in the origin of this PCE, and we propose a mechanism based on the light-induced lowering of the domain wall pinning energy. The PCE is local and reversible, allowing writing and erasing of magnetic images using light.
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: H
authors.initials: H
authors.lastname: Hoffmann
authors.forename: V L
authors.initials: VL
authors.lastname: Korenev
authors.forename: T
authors.initials: T
authors.lastname: Kiessling
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