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Optical absorption and photoluminescence spectroscopy of the growth of silver nanoparticles

P. Gangopadhyay·R. Kesavamoorthy·Santanu Bera·P. Magudapathy·K. G. M. Nair·B. K. Panigrahi·S. V. Narasimhan
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Abstract

Results obtained from the optical absorption and photoluminescence (PL) spectroscopy experiments have shown the formation of excitons in the silver-exchanged glass samples. These findings are reported here for the first time. Further, we investigate the dramatic changes in the photoemission properties of the silver-exchanged glass samples as a function of postannealing temperature. Observed changes are thought to be due to the structural rearrangements of silver and oxygen bonding during the heat treatments of the glass matrix. In fact, photoelectron spectroscopy does reveal these chemical transformations of silver-exchanged soda glass samples caused by the thermal effects of annealing in a high vacuum atmosphere. An important correlation between temperature-induced changes of the PL intensity and thermal growth of the silver nanoparticles has been established in this Letter through precise spectroscopic studies.

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P. Gangopadhyay, R. Kesavamoorthy, Santanu Bera, P. Magudapathy, K. G. M. Nair, B. K. Panigrahi, S. V. Narasimhan. 2005-02-14. Optical absorption and photoluminescence spectroscopy of the growth of silver nanoparticles. https://doi.org/10.1103/physrevlett.94.047403

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