Hole-mediated ferromagnetic enhancement and stability in Cu-doped ZnOS alloy thin films

We report room temperature ferromagnetism enhancement of Cu-doped ZnOS (Zn1-xCuxO1-ySy) alloy thin films with high hole concentration. The Zn0.91Cu0.09O0.92S0.08 alloy thin films with a hole concentration of 4.3 x 10(19) cm(-3) show the strongest magnetization of 1.5 mu B/Cu. First-principles calculation shows that high hole concentration stabilizes the ferromagnetic ordering in the Zn1-xCuxO1-ySy system, indicating a strong correlation between ferromagnetic stability and hole concentration. These results suggest that the Zn1-xCuxO1-ySy alloy with high hole concentration is promising to find applications in spintronic devices.