Spheroidal nanoparticles as thermal near-field sensors

TL;DR

This paper proposes using shape-dependent spheroidal nanoparticles as sensors to enhance nanoscale thermal imaging by extracting directional near-field heat transfer information beyond local density of states.

Contribution

It introduces a novel method employing spheroidal nanoparticles to probe the anisotropic components of thermal near fields for improved nanoscale imaging.

Findings

Shape-dependent nanoparticles can assess correlation tensor components.

Numerical models support the feasibility of the proposed sensing approach.

Enhanced directional information is obtainable beyond local density of states.

Abstract

We suggest to exploit the shape-dependence of the near-field heat transfer for nanoscale thermal imaging. By utilizing strongly prolate or oblate nanoparticles as sensors one can assess individual components of the correlation tensors characterizing the thermal near field close to a nanostructured surface, and thus obtain directional information beyond the local density of states. Our theoretical considerations are backed by idealized numerical model calculations.