Ultrasmall all-optical plasmonic switch and its application to superresolution imaging
Journal
Scientific Reports
Journal Volume
6
Date Issued
2016
Author(s)
Wu, H.-Y.
Huang, Y.-T.
Shen, P.-T.
Lee, H.
Oketani, R.
Yonemaru, Y.
Yamanaka, M.
Shoji, S.
Lin, K.-H.
Kawata, S.
Fujita, K.
Abstract
Because of their exceptional local-field enhancement and ultrasmall mode volume, plasmonic components can integrate photonics and electronics at nanoscale, and active control of plasmons is the key. However, all-optical modulation of plasmonic response with nanometer mode volume and unity modulation depth is still lacking. Here we show that scattering from a plasmonic nanoparticle, whose volume is smaller than 0.001 μm(3), can be optically switched off with less than 100 μW power. Over 80% modulation depth is observed, and shows no degradation after repetitive switching. The spectral bandwidth approaches 100 nm. The underlying mechanism is suggested to be photothermal effects, and the effective single-particle nonlinearity reaches nearly 10(-9) m(2)/W, which is to our knowledge the largest record of metallic materials to date. As a novel application, the non-bleaching and unlimitedly switchable scattering is used to enhance optical resolution to λ/5 (λ/9 after deconvolution), with 100-fold less intensity requirement compared to similar superresolution techniques. Our work not only opens up a new field of ultrasmall all-optical control based on scattering from a single nanoparticle, but also facilitates superresolution imaging for long-term observation.
SDGs
Type
journal article