First Principles Calculation Of Ferromagnetic Properties Of Co, Cu Doped ZnO Nanowire

Zinc Oxide (ZnO), aâ…¡-â…¥group compound semiconductor, is a wide-direct-gap oxide with a band gap of about 3.37eV and a excition binding energy of about 60mV at room temperature. It is transparent in the visible light region. Compared with other wide-gap semiconductors, ZnO is more stable; In addition, it has good electromechanical coupling characteristics and low threshold value of photoluminescence and stimulated radiation. Now, ZnO has been widely used in the field of photoelectric devices, for example the blue-ray and ultraviolet luminescent devices. In particular, properly doped with 3d transition metal elements, ZnO is likely to be a new semiconductor which has good properties of light, electricity and magnetism. These unique properties will make it have great application value in spintronic devices.Up to now, large numbers of research work in 3d transition metal elements doped ZnO has been carried out, however, these researches were mainly concentrated on two aspects:one is about magnetic origins and magnetic coupling mechanism of ZnO-based Diluted Magnetic Semiconductor (DMSs); the other is about new structures of ZnO-based DMSs and its unique physical properties in nanometer scale.In this thesis, the first-principles calculation based on the density functional theory has been performed to investigate the 3d transition metal elements doped ZnO nanowire. First, the structural stability and magnetism of intrinsic ZnO have been studied. Then the ZnO nanowires with a O vacancy or a Zn vacancy were analyzied respectively. Next, Co-doped ZnO and Cu-doped ZnO have been calculated, respectively, at the doping concentration of 2.083%, The most stable doping configuration for them were firstly determined, and then the magnetic properties were calculated. Last, Co and Cu co-doped ZnO nanowires had been calculated with the most stable doping configurations, and then their magnetic properties were analyzed.