The study of the behavior of Al impurity in ZnO lattice by a fullerene like model

The fullerene like Zn32Al4O36 clusters were investigated and the oxygen interstitial Oi acceptor intrinsic defect formation energy as well as Al ionization energy were calculated. The effect of lattice packing defects on the electroactivity of Al impurity was investigated. Analysis of the defects formation energies shows the smaller formation energy of interstitial Oi in a comparison with a formation of Zn vacancy. This allows us to formulate recommendations of technological conditions for films deposition, with improved electroactivity of Al donor.

Study on the optical properties for the F-type color center in BeO crystal with first-principles

In this paper, we calculated the defect formation energy of oxygen vacancies with different charge states (0, +1, +2) in beryllium oxide crystal by using density functional theory (DFT). Based on defect formation energy, the positions of charge transition levels are obtained. However, there is a well-known problem that DFT will underestimate the band gap, which leads to the positions of charge transition levels are arguable. To obtain more accurate charge transition levels, we employ the hybrid functionals (HSE) to relieve the band edge problem, as well as use the finite-size corrections (FNV) to correct the defect formation energy. After obtaining the location of the charge transition level, we obtain a reliable description of the optical line shape of the F/F[Formula: see text] center containing electron–phonon coupling. The absorption spectra of the F center and F[Formula: see text] center peak at 7.1 eV and 6.3 eV, respectively. The luminescence band of the F center peaks at 4.7 eV. Furthermore, we speculate that the luminescence band near 3.7 eV is assigned to the F[Formula: see text] center.

Tuning magnetism by biaxial strain in native ZnO

Strain conditions have little effect on the defect formation energy of Zn and O vacancies in ZnO, but they do affect the magnetism significantly.