Bound exciton luminescence in ZnSe under hydrostatic pressure

We report pressure‐dependent photoluminescence (PL) measurements on ZnSe single crystals grown by the seeded physical vapor phase transport technique. Two kinds of ZnSe samples, the as‐grown and Zn‐extracted single crystals were used in this study. The Id1 line is the predominant spectral feature for the as‐grown samples and shifts with pressure at a rate of 7.3 meV/kbar. The I3 emission dominates the PL spectra of the Zn‐extracted samples and has a pressure coefficient of 6.6 meV/kbar, which is inconsistent with the assumption of the I3 line originating from the recombination of the excitons bound to ionized donors.