The influence of intrinsic atomic defects on the electronic and optical properties of the single layer AlN

In this paper, we present first-principles calculations of the electronic, magnetic, and optical properties of the defective single layer AlN. Our calculations based on density functional theory demonstrate that the vacancy defects, such as removing one N atom or one Al atom from single layer AlN lead to asymmetric conditions in the transmission spectrum and semimetallic behavior. However, the single layer AlN in the presence of one N vacancy with one Al vacancy shows the semiconducting nature. The band gap for this structure is narrower than that of pristine structure. In addition, the optical analysis of the pristine structure shows that the first peak of the imaginary part of the dielectric function corresponds to the band gap energy and the presence of a defect in this structure affects the position of peaks of its imaginary part. Moreover, we obtain the defect formation energy and magnetic moment for the various point defects. These results can be useful insights to utilize in nano/optoelectronic and spintronic applications.