Nonlinear scattering in gold nanospheres

Po Ting Shen, Cheng Wei Lin, Hsiang Lin Liu, Shi Wei Chu

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

Nonlinearity enhanced by noble metallic nanoparticles provide novel light manipulation capabilities and innovative applications. Recently, we discovered a new nonlinear phenomenon on the scattering of metallic nanoparticles by continuous-wave (CW) lasers at the intensity around MW/cm2 and applied to super-resolution microscopy that allowed spatial resolution of plasmonic nanostructures down to λ/8. However, its mechanism is still unknown. In this work, we elaborate the mechanism behind the nonlinear scattering of gold nanospheres. There are four possible candidates: intraband transition, interband transition, hot electron, and hot lattice. Each of them has a corresponding nonlinear refractive index (n2), which is related to temporal dependence of its light-matter interaction. We first measure the intensity dependence of nonlinear scattering to extract the effective n2 value. We find out it has the closest n2 value to hot lattice, which causes either the shift or weakening of the surface plasmon resonance (SPR). To further verify the mechanism, the nanospheres are heated up with both a hot plate and a CW laser, and the variation of single-particle SPR scattering spectra are measured. In both cases, more than 50% reduction of scattering is observed, when temperature rises a few tens of degrees or when illumination intensity reaches the order of 1MW/cm2. Thus, we conclude the spectra variation by the two different heating source, as well as the nonlinear scattering are all due to hot lattice, and subsequent permittivity change with temperature. The innovative concept of hot lattice plasmonics not only opens up a new dimension for nonlinear plasmonics, but also predicts the potential of similar nonlinearity in other materials as long as their permittivity changes with temperature.

Original languageEnglish
Title of host publicationPhysics and Simulation of Optoelectronic Devices XXIV
EditorsYasuhiko Arakawa, Bernd Witzigmann, Marek Osinski
PublisherSPIE
ISBN (Electronic)9781628419771
DOIs
Publication statusPublished - 2016 Jan 1
EventPhysics and Simulation of Optoelectronic Devices XXIV - San Francisco, United States
Duration: 2016 Feb 152016 Feb 18

Publication series

NameProceedings of SPIE - The International Society for Optical Engineering
Volume9742
ISSN (Print)0277-786X
ISSN (Electronic)1996-756X

Other

OtherPhysics and Simulation of Optoelectronic Devices XXIV
CountryUnited States
CitySan Francisco
Period16/2/1516/2/18

Keywords

  • Continuous-Wave Laser
  • Hot Lattice Plasmonics
  • Nonlinear Plasmonics
  • Nonlinear Scattering
  • Saturation And Reverse Saturation
  • Surface Plasmon Resonance

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Computer Science Applications
  • Applied Mathematics
  • Electrical and Electronic Engineering

Fingerprint Dive into the research topics of 'Nonlinear scattering in gold nanospheres'. Together they form a unique fingerprint.

  • Cite this

    Shen, P. T., Lin, C. W., Liu, H. L., & Chu, S. W. (2016). Nonlinear scattering in gold nanospheres. In Y. Arakawa, B. Witzigmann, & M. Osinski (Eds.), Physics and Simulation of Optoelectronic Devices XXIV [97421G] (Proceedings of SPIE - The International Society for Optical Engineering; Vol. 9742). SPIE. https://doi.org/10.1117/12.2209297