Scattering of 130 nm radiation with 100 fs pulse length was used to monitor the α/β-striped microstructure in MnAs/GaAs(001), after a 390 nm 5 mJcm−2 pump pulse. A strong reduction of the Bragg peak intensity, corresponding to a widening of the β-stripes, takes place with a characteristic time of 15 ps. These results are relevant within the context of using MnAs/GaAs(001) as a template for the growth of ferromagnetic films, whose magnetization direction can be controlled by modifying the template temperature.