Structural, and magnetic properties of Europium doped (ZnO)<inf>12</inf> clusters

Abstract

ZnO-based dilute magnetic semiconductors (DMSs) have attracted wide interest because of their potential application in developing spintronic devices such as spin field effect transistors and spin light emitting diodes [1,2]. The DMSs are mainly manipulated via doping in bulk phase ZnO materials, which, however, has the handicaps of low composition rate and local fluctuations. Compared with bulk and film, cluster always exhibits special physical and chemical properties due to its size effect and large surface-to-volume ratio, which also makes the doping easier to achieve. Thus, the limited impurity concentration encountered in bulk may be overcome by assembling stable doped cluster to synthesize a new class of DMS. Previous theoretical studies indicated that (ZnO)12 cluster is a particularly stable cage [3-5]. Thus, this structure can be taken as a good precursor for the investigation of doped ZnO clusters [6-7]. In this paper, we have carried out a systematical theoretical investigation on the structural, electronic, and magnetic properties of (ZnO)12 clusters doped with one or two Europium (Eu) atoms based on the density functional theory methods.