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arXiv · 2408.12261

Core-Shell Nanoparticle Resonances in Near-Field Microscopy Revealed by Fourier-demodulated Full-wave Simulations

Dinghe Dai·Richard Ciesielski·Arne Hoehl·Bernd Kaestner·Dario Siebenkotten
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Abstract

We present a detailed investigation of the near-field optical response of core-shell nanoparticles using Fourier-demodulated full-wave simulations, revealing significant modifications to established contrast mechanisms in scattering-type scanning near-field optical microscopy (s-SNOM). Our work examines the complex interplay of geometrical and optical resonances within core-shell structures. Using a finite element method (FEM) simulation closely aligned with the actual s-SNOM measurement processes, we capture the specific near-field responses in these nanostructures. Our findings show that core-shell nanoparticles exhibit unexpected distinct resonance shifts and massively enhanced scattering driven by both core and shell properties. This investigation not only advances the understanding of near-field interactions in complex nanosystems but also provides a refined theoretical framework to accurately predict the optical signatures of nanostructures with internal heterogeneity.

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Dinghe Dai, Richard Ciesielski, Arne Hoehl, Bernd Kaestner, Dario Siebenkotten. 2024-08-22. Core-Shell Nanoparticle Resonances in Near-Field Microscopy Revealed by Fourier-demodulated Full-wave Simulations. https://arxiv.org/abs/2408.12261

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