Ferromagnetic (Mn, N)-codoped ZnO nanopillars array: Experimental and computational insights

To reveal the mechanism responsible for ferromagnetism in transition metal and hole codoped oxide semiconductors, we carry out a comparative study on Mn-doped and (Mn, N)-codoped ZnO nanopillars. Compared with Mn-doped ZnO samples, (Mn, N)-codoped ZnO nanopillars exhibit an enhanced room temperature ferromagnetism. The modulation of bound magnetic polarons via Mn and N codoping corroborates the correlation between the ferromagnetism and hole carriers, which is also verified by first-principles density functional theory calculations. Our study suggests that the electronic band alteration as a result of codoping engineering plays a critical role in stabilizing the long-range magnetic orderings. (C) 2014 AIP Publishing LLC.