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Updated: Jun 22, 2026

Measurement of Coherence Decay in GaMnAs Using Femtosecond Four-wave Mixing
Published on: December 3, 2013
Nonthermal photocoercivity effect in a low-doped (Ga,Mn)As ferromagnetic semiconductor
G V Astakhov1, H Hoffmann, V L Korenev
1Physikalisches Institut (EP3), Universität Würzburg, 97074 Würzburg, Germany. astakhov@physik.uni-wuerzburg.de
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.
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