High-resolution 3D phase-contrast imaging beyond the depth of field limit via ptychographic multi-slice electron tomography

TL;DR

This paper demonstrates atomic-resolution 3D phase-contrast imaging beyond the depth of field limit using multi-slice ptychographic electron tomography, achieving high-resolution reconstructions of nanostructures.

Contribution

It introduces a novel application of multi-slice ptychography for 3D imaging beyond the depth of field limit in electron microscopy.

Findings

Achieved 1.75 Å resolution in a (18.2 nm)^3 volume.

Successfully reconstructed a Co3O4 nanocube using tilt-series 4D-STEM.

Surpassed traditional depth of field limitations in 3D electron imaging.

Abstract

Resolving single atoms in large-scale volumes has been a goal for atomic resolution microscopy for a long time. Electron microscopy has come close to this goal using a combination of advanced electron optics and computational imaging algorithms. However, atomic-resolution 3D imaging in volumes larger than the depth of field limit of the electron optics has so far been out of reach. Electron ptychography, a computational imaging method allowing to solve the multiple-scattering problem from position- and momentum-resolved measurements, provides the opportunity to surpass this limit. Here, we experimentally demonstrate atomic resolution three-dimensional phase-contrast imaging in a volume surpassing the depth of field limits using multi-slice ptychographic electron tomography. We reconstruct tilt-series 4D-STEM measurements of a Co3O4 nanocube, yielding 1.75 {\AA} resolution in a reconstructed volume of (18.2nm)^3.