Stress effects on excitons bound to neutral acceptors in InP

Abstract

We present stress-dependent photoluminescence measurements on excitons bound to neutral acceptors in InP. We analyze the experimental results in two theoretical schemes: a $j\ensuremath{-}j$ coupling scheme and a crystal-field scheme. We find that the triplet structure of the (${A}^{0}X$) complex results from hole-hole coupling in the cubic crystal field. We show that the three bound-exciton states correspond to ${\ensuremath{\Gamma}}_{8},{\ensuremath{\Gamma}}_{7,8}, \mathrm{and} {\ensuremath{\Gamma}}_{6}$ in order of increasing energies, the electron-hole exchange energy being found to be vanishingly small.