PREFERENTIAL DONOR-ACCEPTOR PAIRING RESULTS FOR ZNSE-NA

Preferential pairing between donors and acceptors, which results from the Coulomb attraction between ionized donors and acceptors, has frequ ently been suggested, but has been very difficult to establish conclus ively. We here report definitive identification of such preferential p airing, from donor-acceptor pair luminescence. We observed identical c lose pair lines (both in location and in relative intensity) in two sa mples of Na-doped ZnSe, but the associated distant pair peak was obser ved at different energies in the two samples. We explain this by assum ing that there is strong preferential pairing in one sample and weak o r random pairing in the other.