Mysterious absence of pair luminescence in gallium phosphide bismide. (7th May 2015) - Christian, Theresa M.
Abstract: Gallium phosphide bismide (GaP1− x Bi x ) epilayers with x up to 1.0% were grown via molecular beam epitaxy and their photoluminescence spectra were investigated at low temperatures. Surprisingly, the emission spectrum of the GaP1− x Bi x epilayers was fully described by isolated bismuth-bound exciton recombination at the A and B lines (2.232 and 2.229 eV, respectively) together with their phonon replicas, without a need for any description of recombination from bismuth pair or cluster states. These observations contrast with the typical behavior of energy transfer to lower-lying nitrogen pair states in GaP1− y N y at similar impurity concentrations and offer insights into the electronic structure evolution of GaP1− x Bi x .