Excited states of bound excitons in wurtzite-type semiconductors

✍ Scribed by J. Puls; F. Henneberger; J. Voigt

• Publisher: John Wiley and Sons
• Year: 1983
• Tongue: English
• Weight: 557 KB
• Volume: 119
• Category: Article
• ISSN: 0370-1972
• DOI: 10.1002/pssb.2221190133

✦ Synopsis

Abstract

Excitons bound to neutral impurities are studied with respect to excited states by means of excitation spectroscopy in CdS single crystals at 1.8 K. The symmetry of the four excited states of the exciton bound to neutral donor (placed energetically below the free exciton) can be deduced from the observed dependence of their optical transitions on the direction of the wave vector and the polarization. Theoretical considerations taking into account the complex valence band structure of wurtzite‐type semiconductors lead to an explanation of these states in terms of excited (p‐ and d‐like) hole states of the bound exciton. With respect to the exciton bound to neutral acceptor only the well‐known I~1B~‐states are found experimentally arising from the incorporation of a hole from the lower B‐subvalence band in the complex.