Photothermal Microscopy and
Spectroscopy Webinar

In the last decade, optical nanoantennas have revolutionized light manipulation and control at the nanoscale. Light absorption was initially considered a purely detrimental process, reducing the efficiency of optoelectronic devices. Recently, however, it has attracted growing interest, enabling novel light-energy conversion pathways and offering intriguing opportunities for reconfigurable systems. 

In this talk, I will discuss self-induced optical heating effects in highly absorbing Silicon (Si) and Germanium (Ge) nanoresonators. In particular, I will show recent calculations demonstrating that, due to thermo-optical effects, self-heating can give rise to a complex, non-linear relationship between illumination intensity and temperature, even for moderate illumination intensities relevant for applications such as Raman scattering [1]. Subsequently, I will discuss how self-induced optical heating could be employed for thermally reconfigurable optical devices and metasurfaces [2]. Finally, I will discuss our recent effort in controlling the temperature field in multi-dimensional arrays of nanoantennas, highlighting the importance and opportunities offered by thermo-optical effects [3].

1. T. V. Tsoulos, G. Tagliabue, Nanophotonics 9, 3849–3861 (2020).
2. A. Archetti, R. J. Lin, N. Restori, F. Kiani, T. V. Tsoulos, G. Tagliabue, Nanophotonics 11, 3969–3980 (2022)
3. A. Naef, T. V. Tsoulos, G. Tagliabue, Adv. Opt. Mater. 11 (2023).