Ferromagnetic ordering of Mn diluted into InAs(100) probed by x-ray magnetic circular dichroism

This work reports ferromagnetic ordering of manganese atoms diluted into InAs(100), as seen by X-ray magnetic circular dichroism (XMCD). Room-temperature grown Mn layers on InAs(100) are not magnetic, whereas upon annealing at 250 degrees C, Mn migrates into the semiconductor and exhibits a clear XMCD signal. The net ordered Mn magnetic moment is found to be about 0.7 mu(B) at low temperatures, whereas the Mn atoms are in a state characterized by a local spin of about 2 mu(B). The temperature dependence of the Mn net magnetic moment gives a Curie temperature of more than 150 K, which is higher than the values reported so far for (In,Mn)As and (Ga, Mn)As diluted magnetic semiconductors.