Premium
Mechanical Deformation–Assisted Fabrication of Plasmonic Nanobowties with Broken Symmetry and Tunable Gaps
Author(s) -
Liu YueFeng,
Zhang Runyu,
Braun Paul V.
Publication year - 2020
Publication title -
particle and particle systems characterization
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.877
H-Index - 56
eISSN - 1521-4117
pISSN - 0934-0866
DOI - 10.1002/ppsc.201900463
Subject(s) - materials science , raman scattering , substrate (aquarium) , raman spectroscopy , fabrication , plasmon , polarization (electrochemistry) , deformation (meteorology) , lithography , scattering , nanotechnology , optoelectronics , optics , composite material , chemistry , medicine , oceanography , physics , alternative medicine , pathology , geology
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).