Room-temperature ferromagnetism in highly Cr-doped II-Mn-VI magnetic semiconductor Cd sub(1-x-y)Mn sub(x)Cr sub(y)Te

We describe structural, magnetic, and transport properties of the Cd sub(1-x-y)Mn sub(x)Cr sub(y)Te ferromagnetic semiconductor alloy. Bulk Cd sub(1-x-y)Mn sub(x)Cr sub(y)Te crystals containing up to 10% of Cr (y = 0.10) were grown by the Bridgman method and were found to be strongly p type and ferromagnetic, with the highest Curie temperature of 362 K observed for y = 0.10. Magnetotransport measurements reveal the presence of the anomalous Hall effect up to and above room temperature, providing evidence that the observed ferromagnetism is characteristic of bulk Cd sub(1-x-y)Mn sub(x)Cr sub(y)Te. Our experiment data suggest that Cr ions play a crucial role in establishing ferromagnetism in this quaternary alloy.