Bound magnetic polaron driven low-temperature ferromagnetism in Cu1−xMnxO compounds

Partial Mn atoms have been confirmed to enter the CuO lattice and form the Cu1−xMnxO compounds in the case of doping with 0≤x≤0.2 by the sol-gel method. With increasing Mn content, magnetism is observed. The magnetic critical transition temperature increases with enhanced magnetism, which obeys the bound magnetic polaron theory. The electronic transportation shows an insulating behavior as the band-gap decreases. Our results may indicate that CuO may be used as a candidate of magnetic semiconductor.