Coherently photoinduced ferromagnetism in diluted magnetic semiconductors

Ferromagnetism is predicted in undoped diluted magnetic semiconductors illuminated by intense sub-band-gap laser radiation . The mechanism for photoinduced ferromagnetism is coherence between conduction and valence bands induced by the light which leads to an optical exchange interaction. The ferromagnetic critical temperature TC depends both on the properties of the material and on the frequency and intensity of the laser and could be above 1K.

This work has been supported by the Welch Foundation, the Office of Naval Research under grant N000140010951, DARPA/ONR N0014-99-1-1096, NSF DMR 0099572, DMR-0312491, Ministerio de Ciencia y Tecnología, MAT2003-08109-C02-01, and Ramón y Cajal program (MCYT). This has been partly funded by FEDER funds.