Engineering light-driven thermal landscapes at the nanoscale

Controlling and understanding thermal energy at the nanoscale is a key challenge in nanoscience, with broad implications for semiconductor technology, photocatalysis, and light-activated medicine. Plasmonic nanostructures offer a powerful approach to achieve sub-wavelength photothermal confinement by converting light into localized heat. In this review, we first examine the fundamental mechanisms of plasmonic light-to-heat conversion and how both classical and non-Fourier heat transfer models describe the spatiotemporal evolution of temperature. We then explore how advances in material science, nanophotonic architectures, and micro-environmental engineering have opened up new opportunities for achieving faster and more localized thermal gradients. Finally, we briefly assess the capabilities and limitations of current nanothermometry techniques for resolving temperature with nanometer precision and at ultrafast timescales.