A Win-Win Effect for Both the Ferromagnetism and the Dopability of p-Type Doping in ZnO:(Cu+N)

We investigate the electronic structures and magnetic properties of ZnO doped with N, Cu, and (Cu+N) by using a first principles method and considering the strong correlation effect. It is interesting to compare these three systems. ZnO:N has weak p-type doping and unstable ferromagnetism, while ZnO:Cu becomes insulating due to the Jahn–Teller effect. Cu and N codoping can not only greatly improve the dopability of p-type doping accompanying the Jahn–Teller fading, but also enhance the ferromagnetism at the same time. The calculation results indicate that there is a win-win effect between N and Cu dopants in the ZnO:(Cu+N) system, which could possibly find applications in spintronics besides optoelectronics.