The effect of defects on Cu-doped CdS: A first-principles study

With the first-principles method based on the density functional theory (DFT), we study the effect of defects on Cu-doped CdS. A single Cd vacancy, S vacancy or Cd interstitial is inserted into the Cd34Cu2S36 crystal structure, respectively. Band structures and the density of states (DOS) are calculated to investigate the effect of various defects on the electronic structures, which are considered to be associated with magnetic properties and optical properties. It turns out that the Cd vacancy, S vacancy and Cd interstitial have a significant influence on the ferromagnetic (FM) stability and optical properties. These results provide an approach to utilize Cu-doped CdS-based materials used as spintronics and optoelectronic devices efficiently.