Codoping: A possible pathway for inducing ferromagnetism in ZnO
نویسندگان
چکیده
A detailed ab initio DFT/GGA and DFT /GGA+U investigation of codoping ZnO with Co and Cu ions reveals the role of Cu and the existence of optimum structural dopant configurations which could lead to the enhancement of ferromagnetism. The role of the Cu ions in Zn Co,Cu O is to act as superexchange mediators while causing a remote delocalization through the hybridization of the Cu d3z2−r2 spin-majority states with the O p states, thereby enhancing the ferromagnetism. The ferromagnetic state is found to be more favorable than the antiferromagnetic one if the Cu-d band is spin splitted. Such a process is reminiscent of the conventional RKKY interaction among magnetic impurities embedded in a metal.
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