Open AccessSoret effect and photochemical reaction in liquids with laser-induced local heating
Author(s) -
L. C. Malacarne,
Nelson G. C. Astrath,
A. N. Medina,
Leandro S. Herculano,
Mauro Luciano Baesso,
P. R. B. Pedreira,
Jun Shen,
Qi Wen,
K. Michaelian,
Craig Fairbridge
Publication year - 2011
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.19.004047
Subject(s) - laser , diffusion , materials science , refractive index , photochemistry , optics , aqueous solution , dye laser , eosin , excitation , thermal , work (physics) , chemistry , optoelectronics , thermodynamics , physics , medicine , staining , pathology , quantum mechanics
We report a theoretical model and experimental results for laser-induced local heating in liquids, and propose a method to detect and quantify the contributions of photochemical and Soret effects in several different situations. The time-dependent thermal and mass diffusion equations in the presence and absence of laser excitation are solved. The two effects can produce similar transients for the laser-on refractive index gradient, but very different laser-off behavior. The Soret effect, also called thermal diffusion, and photochemical reaction contributions in photochemically reacting aqueous Cr(VI)-diphenylcarbazide, Eosin Y, and Eosin Y-doped micellar solutions, are decoupled in this work. The extensive use of lasers in various optical techniques suggests that the results may have significance extending from physical-chemical to biological applications.