  We present superparamagnetic clusters of structurally highly disordered
Co-Zn-O created by high fluence Co ion implantation into ZnO (0001) single
crystals at low temperatures. This secondary phase cannot be detected by common
x-ray diffraction but is observed by high-resolution transmission electron
microscopy. In contrast to many other secondary phases in a ZnO matrix it
induces low-field anomalous Hall effect and thus is a candidate for
magneto-electronics applications.
