  We prepared Ga0.95Mn0.05As films on top of periodic arrays of InAs quantum
dots. X-ray diffraction reveals periodically strained films, commensurate to
substrate's patterning. The dots produce a tensile strain in GaMnAs while
between the dots strain is compressive. Our experiments confirm that the
average tensile strain in the film increases with decreasing dots separation.
This trend in strain is accompanied by an increase of the out-of-plane
magnetization component familiar from the established relation between strain
and magnetic anisotropy in GaMnAs films. Our work provides a new route for
controlling magneto-crystalline anisotropies in GaMnAs on a nanometer scale.
