Nanoscale control of optical heating in complex plasmonic systems

Area of Science:

• Plasmonics
• Nanotechnology
• Computational Physics

Background:

• Plasmonic systems offer unique light-matter interactions at the nanoscale.
• Understanding and controlling heat distribution in these systems is crucial for advanced applications.
• Existing methods may lack the precision for complex geometries and assemblies.

Purpose of the Study:

• To introduce a novel numerical technique for analyzing temperature distribution in complex plasmonic systems.
• To demonstrate nanoscale temperature control in individual and assembled nanoparticles.
• To explore potential applications in materials processing and nanoscale actuation.

Main Methods:

• Utilizing a time-efficient boundary element method for coupled electromagnetic and thermodynamic calculations.
• Investigating individual plasmonic particles of various morphologies (ellipsoids, rods, disks, rings).
• Simulating nanoparticle assemblies, including dimers and chains, to analyze inter-particle thermal effects.

Main Results:

• Introduction of a 'thermal capacitance' concept for assessing temperature increase based on absorption cross-section.
• Development of universal thermal-capacitance curves for different particle shapes.
• Demonstration of highly non-uniform nanoscale temperature distributions and precise control over neighboring particle temperatures by tuning light parameters.

Conclusions:

• The developed numerical technique provides a powerful tool for investigating plasmonic system thermal behavior.
• Precise nanoscale temperature control is achievable, opening avenues for selective thermal activation and manipulation.
• Potential applications include dynamic material patterning, targeted chemical reactions, and nanoscale mechanical motion generation.