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Lorentz microscopy of optical fields.

ABSTRACT: In electron microscopy, detailed insights into nanoscale optical properties of materials are gained by spontaneous inelastic scattering leading to electron-energy loss and cathodoluminescence. Stimulated scattering in the presence of external sample excitation allows for mode- and polarization-selective photon-induced near-field electron microscopy (PINEM). This process imprints a spatial phase profile inherited from the optical fields onto the wave function of the probing electrons. Here, we introduce Lorentz-PINEM for the full-field, non-invasive imaging of complex optical near fields at high spatial resolution. We use energy-filtered defocus phase-contrast imaging and iterative phase retrieval to reconstruct the phase distribution of interfering surface-bound modes on a plasmonic nanotip. Our approach is universally applicable to retrieve the spatially varying phase of nanoscale fields and topological modes.

SUBMITTER: Gaida JH

PROVIDER: S-EPMC10582189 | biostudies-literature | 2023 Oct

REPOSITORIES: biostudies-literature

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Lorentz microscopy of optical fields.

Gaida John H JH Lourenço-Martins Hugo H Yalunin Sergey V SV Feist Armin A Sivis Murat M Hohage Thorsten T García de Abajo F Javier FJ Ropers Claus C

Nature communications 20231017 1

In electron microscopy, detailed insights into nanoscale optical properties of materials are gained by spontaneous inelastic scattering leading to electron-energy loss and cathodoluminescence. Stimulated scattering in the presence of external sample excitation allows for mode- and polarization-selective photon-induced near-field electron microscopy (PINEM). This process imprints a spatial phase profile inherited from the optical fields onto the wave function of the probing electrons. Here, we in ...[more]

PMID: 37848420

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