2004/07/13 by Vitaliy N. Pustovit, Pustovit, Vitaliy N., Tigran V. Shahbazyan +1
Engineering · Materials Science · Physics and Astronomy · #Chalcogenide Semiconductor Thin Films #FOS: Physical sciences #Gold and Silver Nanoparticles Synthesis and Applications #Materials Science (cond-mat.mtrl-sci) #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Quantum Dots Synthesis And Properties #cond-mat.mes-hall #cond-mat.mtrl-sci
paper · pdf · doi:10.48550/arxiv.cond-mat/0407332
6 pages, 4 figures
arxiv created 2004/07/13 · openalex publication_date 2004/07/13 · arxiv updated 2009/12/01 · openalex created_date 2022/09/29 · openalex updated_date 2026/07/28
We study the role of strong electron confinement in surface-enhanced Raman\nscattering from molecules adsorbed on small noble-metal particles. We describe\na new source of Raman signal enhancement which originates from different\nbehavior of sp-band and d-band electron densities near the particle boundary.\nIn small particles, a spillover of sp-electron wave-functions beyond the\nclassical radius gives rise to a thin layer with diminished population of\nd-electrons. In this surface layer, the screening of sp-electrons by d-band\nelectron background is reduced. We demonstrate that the interplay between\nfinite-size and underscreening effects results in an increase of the surface\nplasmon local field acting on a molecule located in a close proximity to the\nparticle boundary. Our calculations, based on two-region model, show that the\nadditional enhancement of Raman signal gets stronger for smaller nanoparticles\ndue to a larger volume fraction of underscreened region.\n