  We demonstrate a scheme for optically patterning nuclear spin polarization in
semiconductor/ferromagnet heterostructures. A scanning time-resolved Kerr
rotation microscope is used to image the nuclear spin polarization that results
when GaAs/MnAs epilayers are illuminated with a focused laser having a Gaussian
profile. Rather than tracking the intensity profile of the laser spot, these
images reveal that the nuclear polarization forms an annular lateral structure
having circular symmetry with a dip rather than a peak at its center.
