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'Spillout' effect in gold nanoclusters embedded in c-Al2O3(0001) matrix

S. Dhara·B. Sundaravel·T. R. Ravindran·K. G. M. Nair·C. David·B. K. Panigrahi·P. Magudapathy·K. H. Chen
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Abstract

Gold nanoclusters are grown by 1.8 MeV Au^\sup{2+} implantation on c-Al\sub{2}O\sub{3}(0001)substrate and subsequent air annealing at temperatures 1273K. Post-annealed samples show plasmon resonance in the optical (561-579 nm) region for average cluster sizes ~1.72-2.4 nm. A redshift of the plasmon peak with decreasing cluster size in the post-annealed samples is assigned to the 'spillout' effect (reduction of electron density) for clusters with ~157-427 number of Au atoms fully embedded in crystalline dielectric matrix with increased polarizability in the embedded system.

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S. Dhara, B. Sundaravel, T. R. Ravindran, K. G. M. Nair, C. David, B. K. Panigrahi, P. Magudapathy, K. H. Chen. 2004-10-27. 'Spillout' effect in gold nanoclusters embedded in c-Al2O3(0001) matrix. https://doi.org/10.1016/j.cplett.2004.10.011

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