Ferromagnetism in Mn-doped CuO

Ferromagnetic properties have been observed in CuO doped with 3.5-15 at. % of Mn. The transition from ferromagnetic to paramagnetic phase at T-C=80 K is associated with the metal-insulator transition. Magnetoresistance is weakly negative in the vicinity of the transition, but positive in a wide range of temperatures below T-C. The experimental results suggest a possibility of interpretation in terms of the Zener double-exchange mechanism and strong electron-phonon interactions. (C) 2003 American Institute of Physics.