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arXiv · 2503.17960

Comparison of near-field light intensities: plasmon nanofocusing vs localized plasmon resonance

Tongyao Li·Andrea Schirato·Taku Suwabe·Remo Proietti Zaccaria·Prabhat Verma·Takayuki Umakoshi
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Abstract

The localized surface plasmon resonance of metallic nanostructures produces strongly localized and enhanced near-field light, significantly contributing to nanophotonics research and applications. Plasmon nanofocusing represents another method for generating near-field light through the propagation and condensation of plasmons on tapered plasmonic structures. In both methods, the intensity of near-field light is a critical aspect for many applications. In this study, we numerically inspect and compare the intensities of near-field light generated by either localized plasmon resonance or plasmon nanofocusing. To account for the light-induced changes in the optical properties of plasmonic structures, which in turn influence the near-field light intensity, we couple electromagnetic and thermal calculations to consider in a fully self-consistent manner the effects of the incident light and the light-induced temperature rise within the metal. A gold nanorod and a cone were adopted for exciting the localized plasmon resonance and plasmon nanofocusing, respectively. We find that plasmon nanofocusing generates approximately 1.5 times as strong near-field light as localized plasmon resonance. Our research provides a necessary foundation for generating near-field light, which is crucial for advancing the applications of near-field optics.

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Tongyao Li, Andrea Schirato, Taku Suwabe, Remo Proietti Zaccaria, Prabhat Verma, Takayuki Umakoshi. 2025-03-23. Comparison of near-field light intensities: plasmon nanofocusing vs localized plasmon resonance. https://arxiv.org/abs/2503.17960

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