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arXiv · 0709.1773

Deformation potential dominated phonons in ZnS quantum dots

S. Dhara·A. K. Arora·Jay Ghatak·K. H. Chen·C. P. Liu·L. C. Chen·Y. Tzeng·Baldev Raj
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Abstract

Strong deformation potential (DP) dominated Raman spectra are reported for quantum confined cubic ZnS nanoclusters under off-resonance conditions allowed only in quantum dots. A flurry of zone boundary phonons is demonstrated in the scattering process. Transverse optic (TO) mode in the multi-phonon process shows only even order overtones suggesting the dominance of a two-phonon process (having large DP value in ZnS) and its integral multiples. Two-phonon TO modes corresponding to A1 and B2 symmetries are also demonstrated under off-resonance conditions which are allowed only in quantum dots.

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S. Dhara, A. K. Arora, Jay Ghatak, K. H. Chen, C. P. Liu, L. C. Chen, Y. Tzeng, Baldev Raj. 2008-07-06. Deformation potential dominated phonons in ZnS quantum dots. https://arxiv.org/abs/0709.1773

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