Mechanical Deformation–Assisted Fabrication of Plasmonic Nanobowties with Broken Symmetry and Tunable Gaps

Abstract

A symmetry broken and gap tunable gold nanobowtie array is demonstrated by nanosphere lithography performed on a mechanically uniaxially prestretched elastomeric substrate. Due to symmetry breaking of each nanotriangle with its three neighboring nanotriangles once the uniaxial prestretch is released, the structure exhibits polarization‐dependent optical properties. In addition, the decrease in the gap between adjacent triangles provided by mechanical relaxation of the substrate enhances the electric field enhancement between adjacent triangles, which in turn results in enhanced Raman scattering from molecules present in the gap. Triangle apex‐to‐apex gaps as small as 20 nm are generated using a colloidal crystal formed from 500 nm colloids on at 30% prestretched substrate (gaps formed when an unstretched substrate is used are ≈115 nm).

Document Details

Document Type
Pub Defense Publication
Publication Date
Dec 18, 2019
Source ID
10.1002/ppsc.201900463

Entities

People

  • Paul V Braun
  • Runyu Zhang
  • Yue‐feng Liu

Organizations

  • Air Force Office of Scientific Research
  • China Postdoctoral Science Foundation
  • Jilin University
  • University of Illinois Urbana–Champaign

Tags

Fields of Study

  • Physics

Readers

  • Materials Science and Engineering.
  • Nanofabrication and Microfabrication.
  • Nanoscale Plasmonic Nanotechnology