Spatial confinement of electromagnetic hot and cold spots in gold nanocubes

ACS Nano. 2012 Feb 28;6(2):1299-307. doi: 10.1021/nn2040389. Epub 2012 Feb 1.

Abstract

We report a near-field imaging study of colloidal gold nanocubes. This is accomplished through a photochemical imaging method in which molecular displacements are vectorial in nature, enabling sensitivity to the polarization of the optical near-field of the nanocubes. We analyze the confinement of both electromagnetic hot and "cold" spots with a resolution of λ/35 and emphasize the particularly high spatial confinement of cold spots. The concept of a cold spot complements the well-known electromagnetic hot spot but can have significant advantages. The application of the ultraconfined cold spots to high resolution imaging and spectroscopy is discussed.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Electromagnetic Phenomena*
  • Gold / chemistry*
  • Nanostructures / chemistry*
  • Photochemical Processes
  • Time Factors

Substances

  • Gold