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

We have observed a characteristic modulation in the amplitude of the Shubni kov-de Haas (SdH) oscillations and a large shift of node position with incr easing temperature in the semimagnetic semiconductor Hg1-xMnxTe. The positi ons of the oscillation extrema are almost temperature independent, with the exception that their phase changes by pi after passing the nodal point. Th ese features can be explained in terms of the exchange interaction between conduction electrons and the localized spin moments of Mn ions. The antifer romagnetic temperature and effective spin have been deduced from the temper ature-dependent node position in the SdH oscillations. (C) 2001 American In stitute of Physics.