By using femtosecond time-resolved pump-probe technique we have observed three kinds of coherent phonons (0.30 THz, 1.90 THz, and 3.75 THz) in silver nanoparticles embedded in BaO thin films. The generation of 0.3 THz coherent phonons is attributed to the resonant excitation of localized surface plasmon of silver nanoparticles, and the resonant impulsive stimulated Raman scattering in silver aggregates is responsible for the generation of 1.90 THz and 3.75 THz coherent phonons. But in another area in the same Ag-BaO thin film we only observe 0.3 THz coherent phonons. The space dependence of coherent phonons is attributed to the inhomogeneous distribution of (Ag)_n aggregates.

Date Published: 30 June 1999
PDF: 8 pages
Proc. SPIE 3790, Engineered Nanostructural Films and Materials, (30 June 1999); doi: 10.1117/12.351255

Published in SPIE Proceedings Vol. 3790:
Engineered Nanostructural Films and Materials
Akhlesh Lakhtakia; Russell F. Messier, Editor(s)