Topology Optimization-Based Inverse Design of Plasmonic Nanodimer with Maximum Near-Field Enhancement

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review

13 Scopus Citations
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Author(s)

  • Yiqin Chen
  • Yueqiang Hu
  • Jingyi Zhao
  • Yunsheng Deng
  • Zhaolong Wang
  • Xing Cheng
  • Yongbo Deng
  • Huigao Duan

Detail(s)

Original languageEnglish
Article number2000642
Journal / PublicationAdvanced Functional Materials
Volume30
Issue number23
Online published8 Apr 2020
Publication statusPublished - 4 Jun 2020

Abstract

The near-field enhancement factor is one of the most significant parameters to evaluate the performance of plasmonic nanostructures. Numerous efforts have been made to maximize the enhancement factor through optimizing the size, shape, and spatial arrangement of metallic nanostructures with simple geometries, such as disk, triangle, and rod. This work implements topology optimization to inversely design a metallic nanoparticle dimer with the goal of optimizing the near-field enhancement factor in its sub-10 nm gap. By optimizing the material layout within a given design space, the topology optimization algorithm results in a plasmonic nanodimer of two heart-shaped particles having both convex and concave features. Full-wave electromagnetic analysis reveals that the largest near-field enhancement in the heart-shaped nanoparticle dimer is originated from the greatest concentration of surface charges at the nano-heart apex. Inversely designed heart-, bowtie-, and disk-shaped nanodimers are fabricated by using focused helium ion beam milling with a “sketch and peel” strategy, and their near-field enhancement performances are characterized with nonlinear optical spectroscopies at the single-particle level. Indeed, the heart-shaped nanodimer exhibits much stronger signal intensities than the other two structures. The present work corroborates the validity and effectiveness of topology optimization-based inverse design in achieving desired plasmonic functionalities.

Research Area(s)

  • inverse design, near-field enhancement, nonlinear optics, plasmonic nanostructures, topology optimization

Citation Format(s)

Topology Optimization-Based Inverse Design of Plasmonic Nanodimer with Maximum Near-Field Enhancement. / Chen, Yiqin; Hu, Yueqiang; Zhao, Jingyi; Deng, Yunsheng; Wang, Zhaolong; Cheng, Xing; Lei, Dangyuan; Deng, Yongbo; Duan, Huigao.

In: Advanced Functional Materials, Vol. 30, No. 23, 2000642, 04.06.2020.

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review