Ferromagnetic semiconductors: Ruled by a magnetic-rich minority

The distribution and size of nanomagnetic clusters are controlled during crystal growth to tune ferromagnetic properties of the magnetic semiconductor with spintronic functionality. Extended band states of the semiconductor crystal couple strongly with the local magnetic moments resulting in an enhanced magneto-optical and magneto-electronic response. The mean field theory has been proposed that predicts Curie temperatures above 300 K in wide-bandgap magnetic semiconductor. The studies have shown that ferromagnetism is observed at room temperature by SQUID magnetometry and by using a magneto-optical technique known as magnetic circular dichroism (MCD). The microscopic techniques have been developed to map elemental distribution of thin films to explain the dependency of the Curie temperature and co-doping in a magnetic semiconductor with spintronic functionality.