Abstract
A new class of diluted magnetic semiconductor (DMS) based on III-V compounds and its transport properties are presented. While the new DMS, (In, Mn)As, films exhibiting n-type conduction were all paramagnetic with the Mn–Mn interaction being antiferromagnetic, ferromagnetic interaction between the Mn ions in p-type films manifested itself in the hysteresis in the magnetic field dependence of the Hall resistivity at low temperatures, indicating the presence of ferromagnetic order. This ferromagnetic order was accompanied by paramagnetic response extending to high magnetic fields. The coexistence of remanent magnetization and unsaturated spins (partial ferromagnetic order; asperomagnetism) can be explained by the formation of bound magnetic polarons with partially aligned spins. The ferromagnetic order observed in the (In, Mn)As based heterojunctions is also discussed.