Selective self-optical compensation effect for a newly discovered acceptor-associated emission in Zn+ ion-implanted GaAs

Abstract
Photoluminescence measurements were carried out at 2 K for Zn+ ion‐implanted GaAs, where the concentration of Zn was widely varied from 3×1016 to 1×1021 cm3. Two Zn+‐associated emissions were formed. One emission is at 1.512 eV, g, and the other emission [gg] is just below g and this moves towards the lower energy level with increasing Zn concentration, [Zn]. The intensity of [gg] was enhanced with increasing [Zn], up to [Zn]=3×1017 cm3, and was gradually suppressed for [Zn] beyond that concentration. This selective self‐optical compensation effect (SSOC) for [gg] was found to occur for moderately heavy ion acceptor species such as Zn and Cd, although [gg] is a common emission among many other acceptor impurities. In addition two new emissions were observed between g and [gg] at certain [Zn]. Preliminary theoretical explanations are presented for this SSOC effect.