Photo-thermo-optical modulation of Raman scattering from Mie-resonant silicon nanostructures

Area of Science:

• Nanophotonics
• Optical Spectroscopy
• Materials Science

Background:

• Raman scattering enables non-contact nanoscale thermometry.
• All-dielectric nanostructures, like silicon, enhance photothermal heating via Mie resonances.
• The photo-thermo-optical effect on Raman scattering in resonant nanostructures is underexplored.

Purpose of the Study:

• Investigate the complex photo-thermo-optical effects on Raman scattering in resonant dielectric nanostructures.
• Demonstrate the nonlinear dependence of Raman signal intensity in crystalline silicon nanoparticles.
• Elucidate the role of Mie resonance temperature sensitivity in modulating Raman scattering.

Main Methods:

• Experimental demonstration of photo-thermo-optical interaction.
• Analysis of Raman scattering signal intensity from crystalline silicon nanoparticles.
• Development of a comprehensive model for thermal modulation of Raman scattering.

Main Results:

• Strong photo-thermo-optical interaction leads to nonlinear Raman signal intensity.
• Mie resonance spectral sensitivity to temperature significantly affects heat conversion and Raman efficiency.
• The study reveals a crucial role of thermal reconfiguration of the resonant response.

Conclusions:

• The findings are essential for validating Raman nanothermometry in resonant silicon structures.
• The comprehensive model provides insights into photon-phonon interaction physics in resonant materials.
• Understanding these effects is critical for applications involving resonant nanostructures under strong laser fields.