First-principles calculations of rare earth (RE=Tm, Yb, Ce) doped ZnO: Structural, optoelectronic, magnetic, and electrical properties

A comparative study of wurtzite ZnO doped by rare earth elements (Tm, Yb, Ce) which have been investigated using density functional theory implemented in Wien2K code. The structural parameters were calculated by PBEso1 functional and in good agreement with the experimental data. The electronic and optical properties were determined by TB-mBJ potential. The rare earth elements doped ZnO have a significant impact on the optoelectronic and magnetic properties which mainly arise due to the presence of 4f electrons. The electronic structure shows that the doping of Tm, Yb, Ce on pristine ZnO has increased the band gap, the Fermi level has been shifted to the conduction band, revealing n-type characters. Electrical conductivity has been calculated using BoltzTrap code. It has been observed that the conductivity is improved after doping. Our results provide the basis for future research in (Tm, Yb, Ce) doped ZnO compounds used as integrated optoelectronic devices, solar cells and spintronic applications.