Photothermal Microscopy and
Spectroscopy Webinar

Photothermal heterodyne imaging makes it possible to record pure absorption spectra of individual objects by scanning the pump wavelength. We have implemented such photothermal spectroscopy using a tunable white light laser to record absorption spectra of individual gold nanospheres and nanorods. Recently, we have applied this technique to monitor changes to the plasmon resonance of hybrid nanostructures that consist of a plasmonic core and a semiconducting shell. Comparison to single-particle dark-field scattering spectra allows us to evaluate the plasmon linewidth separately for absorption and scattering, while elucidating effects due to chemical interface damping.