• Applied Science and Convergence Technology
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• 제25권6호
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• pp.158-161
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• 2016

Debye temperature is an important thermodynamical factor in quantum dots (QDs); it can be used to determine the degree of homogeneity of a QD structure as well as to study the interdiffusion mechanism during growth. Direct estimation of the Debye temperature can be obtained using the Varshni relation. The Varshni relation is an empirical formula that can interpret the change of emission energy with temperature as a result of phonon interaction. On the other hand, phonons energy can be calculated using the Fan Expression. The Fan expression and Varshni relation are considered equivalent at a temperature higher than Debye temperature for InAs quantum dot. We investigated InAs quantum dot optically, the photoluminescence spectra and peak position dependency on temperature has been discussed. We applied a mathematical treatment using Fan expression, and the Varshni relation to obtain the Debye temperature and the phonon energy for InAs quantum dots sample. Debye temperature increase about double compared to bulk crystal. We concluded that the In/Ga interdiffusion during growth played a major role in altering the quantum dot thermodynamical parameters.