Antiferromagnetic temperature and effective spin in n-type Hg1-xMnxTe

We have observed a characteristic modulation in the amplitude of the Shubnikov-de Haas (SdH) oscillations and a large shift of node position with increasing temperature in the semimagnetic semiconductor Hg1-xMnxTe. The positions of the oscillation extrema are almost temperature independent, with the exception that their phase changes by pi after passing the nodal point. These features can be explained in terms of the exchange interaction between conduction electrons and the localized spin moments of Mn ions. The antiferromagnetic temperature and effective spin have been deduced from the temperature-dependent node position in the SdH oscillations. (C) 2001 American Institute of Physics.