We propose that is a negatively charged defect center resulting from the "reaction" where represents a substitutional donor. The results of our pseudopotential calculations for Si- and S-induced centers in GaAs indicate large dopant-dependent relaxations leading to threefold-coordinated interstitial sites for either the donor or one of its nearest neighbors. A simple expression for the alloy composition and pressure dependence of the binding energy is suggested and used in an analysis of experimental data.
- Received 24 May 1988
©1988 American Physical Society