Energy-Transfer Processes in Oxygen-Codoped GaAs:Er

Abstract

AbstractGaAs grown by metalorganic chemical vapor deposition and codoped with Er and oxygen shows a simple spectrum with sharp luminescence lines due predominantly to one type of Er center. This center is identified as an Er atom substituting a Ga site, coupled with two oxygen atoms. Photoluminescence measurements under host excitation and photoluminescence excitation measurements that directly excite the 4f-shell of the Er3+ ion indicate that this center is excited much more efficiently than other Er centers simultaneously present in the same sample. A possible energy-transfer mechanism and its implications are discussed.