Optical Near-Field Electron Microscopy

TL;DR

Optical Near-field Electron Microscopy (ONEM) offers a non-invasive, high-resolution imaging method that combines optical probing with electron microscopy, enabling label-free nanoscale imaging without damaging the specimen.

Contribution

This paper introduces ONEM, a novel technique that integrates optical near-field probing with electron microscopy for non-invasive, high-resolution nanoscale imaging.

Findings

Enables label-free nanometric resolution.

Prevents specimen damage during imaging.

Uses optical near-fields converted into electron flux.

Abstract

Imaging dynamical processes at interfaces and on the nanoscale is of great importance throughout science and technology. While light-optical imaging techniques often cannot provide the necessary spatial resolution, electron-optical techniques damage the specimen and cause dose-induced artefacts. Here, Optical Near-field Electron Microscopy (ONEM) is proposed, an imaging technique that combines non-invasive probing with light, with a high spatial resolution read-out via electron optics. Close to the specimen, the optical near-fields are converted into a spatially varying electron flux using a planar photocathode. The electron flux is imaged using low energy electron microscopy, enabling label-free nanometric resolution without the need to scan a probe across the sample. The specimen is never exposed to damaging electrons.