Gold Nanoparticle–Polydimethylsiloxane Thin Films Enhance Thermoplasmonic Dissipation by Internal Reflection

Thermal relaxation dynamics of resonantly excited plasmons is important in optoelectronic, medical, and catalytic applications. This work shows introducing gold nanoparticles (AuNPs) into thin polydimethylsiloxane (PDMS) films enhanced thermoplasmonic dissipation coincident with internal reflection of incident resonant irradiation. Measured thermal emission and dynamics of AuNP–PDMS thin films exceeded emission and dynamics attributable by finite element analysis to Mie absorption, Fourier heat conduction, Rayleigh convection, and Stefan–Boltzmann radiation. Refractive-index matching experiments and measured temperature profiles indicated AuNP-containing thin films internally reflected light and dissipated power transverse to the film surface. Enhanced thermoplasmonic dissipation from metal–polymer nanocomposite thin films could affect opto- and bioelectronic implementation of these systems