Abstract

The magnetic properties of semimagnetic semiconductor (A’= Mn, A = Cd, Zn) are studied. By using the mean field theory in ordered phase and a probability distribution in disordered phase, we have evaluated the nearest neighbouring and the next-neighbouring super-exchange interactions J₁(x) and J₂(x) for  and . The magnetic phase diagram, that is,  versus dilution x, is obtained by the high-temperature series expansions combined with the Padé approximants for the  and systems. A spin glass state has been obtained for . This phase is attributed to the randomness and the frustration of the antiferromagnetic interactions between the  magnetic ions arising from the topology of the diluted magnetic semiconductor alloys.

Key words: Semimagnetic semiconductor, critical temperature, critical exponents, high-temperature series expansions, Padé approximants, phase diagram.