Photothermal Microscopy and
Spectroscopy Webinar

Metallic nanoparticles present strong photothermal responses, meaning that they are efficient nanoscale transducers of light into heat. However, accurately quantifying the temperature increases can be challenging. Anti-Stokes thermometry offers a promising solution by enabling direct and non-invasive temperature measurements of the metal without labeling or prior calibration [1,2]. Here, we present an implementation of Anti-Stokes thermometry that enables the in situ photothermal characterization of individual nanoparticles from a single hyperspectral photoluminescence confocal image [3]. Using this technique, we investigate the link between morphology and light-to-heat conversion of colloidal bimetallic Au/Pd nanoparticles with two different configurations: core–shell and core-satellite [4]. Finally, we discuss the conditions that must be fulfilled for applying Anti-Stokes thermometry to ensembles of nanoparticles, and demonstrate temperature measurements on arrays of Au nanodisks in a collective heating regime [5].

1. X. Xie, D. G. Cahill, Appl. Phys. Lett. 109, 183104 (2016).
2. A. Carattino, M. Caldarola, M. Orrit, Nano Lett. 18, 874–880 (2018).
3. M. Barella et al., ACS Nano 15, 2458–2467 (2021).
4. J. Gargiulo et al., Nat. Commun. 14, 3813 (2023).
5. Ezendam et al., Adv. Optical Mater. 2301496 (2023).