Quantification of ultrafast nonlinear photothermal and photoacoustic effects in molecular thin films via time-domain Brillouin scattering
Abstract
Improving the efficiency of photothermal (PT) therapies and photoacoustic (PA) imaging at the microscopic scale hinges on developing multiphoton-absorbing photothermal molecules or contrast agents that operate in the near-infrared (NIR) range. These advanced agents or molecules will enable excitation with NIR lasers, in an improved transparency range for biological tissues, while enabling minute, highly localized spatial control of the excitation volume. However, progress in this field requires innovative experimental techniques to characterize photothermal and photoacoustic effects under multiphoton excitation. In this article, we showcase a study of a model organometallic molecular compound excited via two-photon absorption (2 PA) using femtosecond laser pulses. Based on a time-domain Brillouin scattering technique, well adapted for investigating ultrafast nonlinear optical absorption processes in ultrathin films on substrates, we determine the effective nonlinear absorption coefficients of the compound directly linked to PT/PA. Our findings provide a practical approach for exploring and optimizing nonlinear PT/PA absorbers and contrast agents.
Article Details
Journal Info
The Journal of Chemical Physics
American Institute of Physics
Authors (13)
Valentin Cherruault
Institut de Physique de Rennes, UMR CNRS 6251, Université de Rennes 1 , 35042 Rennes,
Franck Camerel
Institut des Sciences Chimiques de Rennes, UMR CNRS 6226, Université de Rennes 2 , 35042 Rennes,
Julien Morin
Institut de Physique de Rennes, UMR CNRS 6251, Université de Rennes 1 , 35042 Rennes,
Amédée Triadon
Institut des Sciences Chimiques de Rennes, UMR CNRS 6226, Université de Rennes 2 , 35042 Rennes,
Nicolas Godin
Institut de Physique de Rennes, UMR CNRS 6251, Université de Rennes 1 , 35042 Rennes,
Ronan Lefort
Institute of Physics of Rennes, CNRS-University of Rennes, UMR 6251 1 , F-35042 Rennes,
Olivier Mongin
Institut des Sciences Chimiques de Rennes, UMR CNRS 6226, Université de Rennes 2 , 35042 Rennes,
Jean-François Bergamini
Institut des Sciences Chimiques de Rennes, UMR CNRS 6226, Université de Rennes 2 , 35042 Rennes,
Antoine Vacher
Institut des Sciences Chimiques de Rennes, UMR CNRS 6226, Université de Rennes 2 , 35042 Rennes,
Mark G. Humphrey
Research School of Chemistry
Maciej Lorenc
Institut de Physique de Rennes, UMR CNRS 6251, Université de Rennes 1 , 35042 Rennes,
Frederic Paul
Institut des Sciences Chimiques de Rennes, UMR CNRS 6226, Université de Rennes 2 , 35042 Rennes,
Thomas Pezeril
Institut de Physique de Rennes, UMR CNRS 6251, Université de Rennes 1 , 35042 Rennes,