Bound-Excitonic Emissions in Undoped and Mn-Doped ZnS Single Crystals
Excitonic emissions observed in undoped and Mn-doped ZnS single crystals with cubic modification have been investigated by means of the temperature dependence of photo-luminescence intensity and the doublet structure. Reflectance spectrum at 4.2 K indicates that an exciton dip appears at 3.803 eV and the longitudinal-transverse splitting energy of free exciton is about 4 meV when 4πβ is 1.05×10-2 and ∈ is 8.1, respectively. Thermal dissociation energy of the free exciton is estimated to be about 40 meV. Assuming that the zero-phonon line associated with an Mn emission is ascribed to an isoelectronic-trap bound exciton, the doublet structure and thermal dissociation process are reasonably interpreted.
KeywordsRecombination ZnTe Onic
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- /1/.T. Taguchi, T. Yokogawa and M. Yamashita, Solid State Communication 49 550 (1984).Google Scholar
- /2/.T. Taguchi et al. The 172 nd Electrochemical Society Meeting, Extended Abstract, vol. 87-2 p. 1748 (1987).Google Scholar
- /4/.G.L. Bir, G.E. Pikus, L.G. Suslina and D.L. Fedrov, Sov. Phys. Solid St. 12 2602 (1971).Google Scholar
- /5/.T. Taguchi and B. Ray, Progress and characterisation of crystal growth, ed. B. Pamplin (Pergamon Press, Oxford 1983) p.136.Google Scholar