Energy States of Isolated Donor–Acceptor Pairs and the Influence of Polarization Interaction on the Pair Energy

✍ Scribed by R. Bindemann; K. Unger

• Publisher: John Wiley and Sons
• Year: 1973
• Tongue: English
• Weight: 551 KB
• Volume: 56
• Category: Article
• ISSN: 0370-1972
• DOI: 10.1002/pssb.2220560218

✦ Synopsis

Abstract

Photon energies emitted from donor‐acceptor pairs in semiconductors are calculated using a variational procedure adequate to cover also pairs of small distances. It is shown that beside the Coulomb term the polarization interaction between the two centres is essential. Polarization is involved by spherical trial functions shifted against each other. Symmetrical pairs (with equal binding energies of the isolated impurities) are considered first and asymmetrical ones by a suitable superposition of two symmetrical pairs. The agreement with experimental data taken from GaP is substantially better than the Coulomb term approximation. In the limiting case of vanishing pair distance the calculations give a finite value of the photon energy, which can be interpreted as a free exciton energy.