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Phase-Resolved Surface Plasmon Scattering Probed by Cathodoluminescence Holography.

ABSTRACT: High-energy (1-100 keV) electrons can coherently couple to plasmonic and dielectric nanostructures, creating cathodoluminescence (CL) of which the spectral features reveal details of the material's resonant modes at a deep-subwavelength spatial resolution. While CL provides fundamental insight in optical modes, detecting its phase has remained elusive. Here, we use Fourier-transform CL holography to determine the far-field phase distribution of fields scattered from plasmonic nanoholes, nanocubes, and helical nanoapertures and reconstruct the angle-resolved phase distributions. From the derived fields, we derive the relative strength and phase of induced scattering dipoles. Fourier-transform CL holography opens up a new world of coherent light scattering and surface wave studies with nanoscale spatial resolution.

SUBMITTER: Schilder NJ

PROVIDER: S-EPMC7304075 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Phase-Resolved Surface Plasmon Scattering Probed by Cathodoluminescence Holography.

Schilder Nick J NJ Agrawal Harshal H Garnett Erik C EC Polman Albert A

ACS photonics 20200521 6

High-energy (1-100 keV) electrons can coherently couple to plasmonic and dielectric nanostructures, creating cathodoluminescence (CL) of which the spectral features reveal details of the material's resonant modes at a deep-subwavelength spatial resolution. While CL provides fundamental insight in optical modes, detecting its phase has remained elusive. Here, we use Fourier-transform CL holography to determine the far-field phase distribution of fields scattered from plasmonic nanoholes, nanocube ...[more]

PMID: 32566698

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