The Theoretical And Experimental Analysis Of NiO Doped Cu₂O

Diluted magnetic semiconductors (DMSs) have attracted considerable interest due to the potential use of both the charge and spin of electrons since the last decade. DMSs with practical ordering temperatures could lead to new classes of device and circuits, including spin transistors, ultradense nonvolatile semiconductor memory and optical emitters with polarized output. At beginning most work on DMSs was focused on the traditional compound semiconductors doped with transition metal atoms, such as Mn-doped Ⅲ-Ⅴ-based semiconductors. However, the low Curie temperature is a significant limitation for these materials. Since Sato and Yoshida theoretically predicted in2002the possibility of having materials with ferromagnetism with high-TC(Curie Temperature) using first principle calculations, many efforts have been focused on the search for high-TC ferromagnetism in transitionmetal-doped wide band gap oxide semiconductors such as TiO2, ZnO, and SnO2.Comparing with the above-mentioned transitionmetal-doped oxide semiconductors systems, there are more less reports on the magnetic properties of the Cu2O-based DMSs. Cu2O is one of only a few p-type direct energy band gap (Eg=2.1eV) semiconductors that has a cubic structure with a=4.258A, and its p-type conductivity arises from copper vacancies which introduce an acceptor level,0.5eV above the valence band. And with the versatile properties such as a large exciton binding energy of150meV and a high absorption coefficient for visible light, Cu2O has potential for use in p-n junctions and spin-LEDs.In this paper, we demonstrate room temperature ferromagnetism in doped Cu2O experimentally and theoretically. First we used VASP to calculate the different elements doped Cu2O by adopting the first principle method based on density functional theory. The result show that the Cu2O of doping1%Ni has strong ferromagnetism with good temperature performance. So we choose1%NiO doped Cu2O as the research object for experiment. Compare to other methods, the physical solid phase method is simple and not easy to have chemical or physical pollution, which is adopted in this paper. When we got the1%NiO doped Cu2O samples, and the pure Cu20samples by using the same experimental method, we test methods like XRD, SEM and PPMS to analysis structure characterization, and magnetic properties of the semples.The experimental results is consistent with the theoretical analysis.1%NiO doped Cu20samples represent strong magnetic even in room temperature. So1%NiO doped Cu20is one kind of useable DMSs which has potential for use in the electron spin devices.