“…Recent progress in epitaxy, contamination-free processing, and (nano)characterization [2][3][4][5] allowed the preparation of Ga 1−x Mn x N films with the randomly distributed Mn 3+ ions up to x = 0.1 showing T C up to about 13 K [6] despite the absence of itinerant carriers. A high degree of crystallinity, a random distribution of the Mn ions, and a weak degree of compensation by residual donors were checked in these samples by a range of electron microscopy, synchrotron radiation, ion beam, optical, and magnetic resonance techniques [2,3,5].…”