Picosecond Self-Induced Thermal Lensing from Colloidal Silver Nanodisks

TitlePicosecond Self-Induced Thermal Lensing from Colloidal Silver Nanodisks
Publication TypeJournal Article
Year of Publication2004
AuthorsMaillard, M, Pileni, M-P, Link, S, EL-Sayed, MA
JournalThe Journal of Physical Chemistry B
Volume108
Issue17
Pagination5230 - 5234
Date Published2004
ISBN Number1520-6106
Abstract

The optical and nonradiative relaxation dynamics of 5 nm thick silver nanodisks with a 25 nm diameter have been investigated in an organic solvent by continuous wave (cw) and femtosecond pump?probe time-resolved spectroscopies. Several surface plasmon absorption bands are observed due to the disk shape of these particles. In the time-resolved experiments, the time dependence of the bleach resulting from femtosecond pulsed excitation is studied. On the 1?3 ps time scale, a decay resulting from electron?phonon relaxation is observed. On a longer time scale (>20 ps), a rise rather than a further decay of the bleach intensity is observed. This is shown to result from the formation of a thermal lens due to the induced thermal gradients produced from heating the organic solvent by the phonon?phonon relaxation processes of the photoexcited nanodisks.The optical and nonradiative relaxation dynamics of 5 nm thick silver nanodisks with a 25 nm diameter have been investigated in an organic solvent by continuous wave (cw) and femtosecond pump?probe time-resolved spectroscopies. Several surface plasmon absorption bands are observed due to the disk shape of these particles. In the time-resolved experiments, the time dependence of the bleach resulting from femtosecond pulsed excitation is studied. On the 1?3 ps time scale, a decay resulting from electron?phonon relaxation is observed. On a longer time scale (>20 ps), a rise rather than a further decay of the bleach intensity is observed. This is shown to result from the formation of a thermal lens due to the induced thermal gradients produced from heating the organic solvent by the phonon?phonon relaxation processes of the photoexcited nanodisks.

URLhttp://dx.doi.org/10.1021/jp049943z
DOI10.1021/jp049943z
Short TitleJ. Phys. Chem. B