Wavelength-dependence of the photothermal efficiency of gold nanoparticles in solution by Z-scan photothermal lens spectroscopy

Julien-Bilal Zinoune (1, 2, 3) , Christophe Cassagne (1, 2) , Martinus H.V. Werts (4, 5, 6) , Matthieu Loumaigne (7, 2) , Mihaela Chis (1, 2) , Georges Boudebs (1, 2)

1 LPHIA - Laboratoire de Photonique d'Angers
2 MATRIX - SFR UA MATéRIauX
3 CERADE ESAIP - ESAIP Centre d’Etudes et de Recherche pour l’Aide à la Décision
4 SATIE-II - Instrumentation et Imagerie
5 ENS Rennes - École normale supérieure - Rennes
6 SATIE - Systèmes et Applications des Technologies de l'Information et de l'Energie
7 MOLTECH-Anjou

Using continuous-wave (cw) single-beam Z-scan technique, the absorption and scattering efficiencies of spherical gold nanoparticles (NPs) of varying diameter are determined experimentally through the thermal lens (TL) effect for three different wavelengths in the blue, the green and the red. The main characteristics of the measurement method are detailed, extending the usual experimental procedure for weak absorption with Gaussian beams to higher absorption with top-hat beams. To confirm the validity of our approach, the experimental TL data were compared to the theoretical values from Mie theory and found to be in good agreement within the experimental errors. As expected, the photothermal efficiency of spherical gold NPs increases with lower diameters and towards shorter wavelengths.

Keywords: Thermal lens, Z-scan, linear absorption, scattering efficiency, Mie theory, gold nanoparticles

Domains: Physics [physics]; Nonlinear Sciences [physics]

Julien-Bilal Zinoune, Christophe Cassagne, Martinus H.V. Werts, Matthieu Loumaigne, Mihaela Chis, et al.. Wavelength-dependence of the photothermal efficiency of gold nanoparticles in solution by Z-scan photothermal lens spectroscopy. Chemical Physics Letters, 2023, 823, pp.140501. ⟨10.1016/j.cplett.2023.140501⟩. ⟨hal-04087188⟩