  To clarify whether or not (Ga,Cr)As is an intrinsic diluted magnetic
semiconductor, a systematic study of the magnetic circular dichroism (MCD) was
carried out for a series of (Ga,Cr)As epilayers grown by the low-temperature
molecular-beam epitaxy technique. The present work provides unambiguous
evidence for the intrinsic ferromagnetism of the (Ga,Cr)As epilayers with all
the necessary properties in accordance with that of a diluted magnetic
semiconductor, especially the hysteresis characteristics, which is opened up in
the magnetic field dependence of MCD.
