Electronic structure and magnetic properties of Cu-doped SnO2 from first-principles study

We have studied the electronic structure of Cu-doped SnO2, with different possible geometrical sites for the Cu dopant, to determine the most favored magnetic properties. Our study shows that each Cu has spin-polarized states in the band gap generating a magnetic moment 2.0 mu(B). We also find Cu impurities tend to form clusters which induces strong ferromagnetism with high Curie temperature, through the same p-d hopping interactions as found in Sr2FeMoO6 [Phys. Rev. Lett. 85, 2549 (2000)]. Doped p-type carriers enhanced the ferromagnetism, while n-type carriers are detrimental to ferromagnetism due to charge compensating effects, indicating that the strong ferromagnetism in Cu-doped SnO2 would be achieved by hole doping. (C) 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim