Intra-4 f -shell luminescence excitation and quenching mechanism of Yb in InP

The excitation and quenching mechanism of intra-4f-shell luminescence of Yb ions incorporated in an InP host is discussed. The discussion is based on experimental results of photoluminescence excitation spectra and photoluminescence time-decay curves for crystals grown by metalorganic chemical vapor deposition and liquid-phase epitaxy. The present as well as previously reported experimental results for samples grown by various methods can be consistently interpreted by considering a recently reported Yb-related acceptorlike electron trap near the conduction-band edge and by taking into account the shallow donor and acceptor as well as Yb concentrations in the samples. A model is proposed which describes the Yb intra-4f-shell excitation and quenching mechanisms for samples with various concentrations of the impurities.