Thermoplasmonics under optically coupled regime: A Numerical Study of Dimers, Nanolenses, and Switchable Clusters

TL;DR

This study demonstrates how optical coupling in plasmonic nanostructures enables precise control over nanoscale heating, with implications for advanced thermoplasmonic applications.

Contribution

It provides a numerical framework for understanding and tuning thermal effects in complex plasmonic nanostructures through hybridization and near-field coupling.

Findings

Polarization and gap distance critically influence thermal output.

Nanolenses can focus heat into sub-diffraction volumes.

Switchable clusters exhibit significant thermal differences.

Abstract

The management of thermal effects in plasmonic nanostructures is frequently viewed as a detrimental waste rather than a useful, controllable entity. We show that optical coupling of plasmonic nanoparticles enables precise spatiotemporal control over nanoscale heating. Through numerical investigation of experimentally-achievable systems from individual nanoparticles and dimers to nanolenses and switchable clusters, we demonstrate how plasmon hybridization and near-field coupling dictate the magnitude and spatial distribution of temperature. Our results highlight the critical role of polarization and gap distance in tuning the thermal output of dimers, the ability of a trimer nanolens to focus heat into a sub-diffraction volume, and the pronounced thermal difference in a switchable nanoparticle cluster. This work establishes a framework for designing advanced thermoplasmonic systems where heat is not merely a detriment, but a dynamically controllable element for applications in catalysis, health, or active photonic devices.