Demonstration of a 2x2 programmable phase plate for electrons

TL;DR

This paper demonstrates a 2x2 programmable phase plate for electrons using electrostatic lenses, enabling dynamic electron probe shaping in TEM, with results closely matching theoretical predictions and potential for advanced beam control.

Contribution

It introduces a novel 2x2 programmable phase plate for electrons, advancing adaptive optics capabilities in transmission electron microscopy.

Findings

Successful experimental realization in TEM at 300 kV

Close agreement between results and theoretical models

Potential for future beam shaping and aberration correction

Abstract

First results on the experimental realisation of a 2x2 programmable phase plate for electrons are presented. The design consists of an array of electrostatic einzel lenses that influence the phase of electron waves passing through 4 separately controllable aperture holes. This functionality is demonstrated in a conventional transmission electron microscope operating at 300~kV and results are in very close agreement with theoretical predictions. The dynamic creation of a set of electron probes with different phase symmetry is demonstrated, thereby bringing adaptive optics in TEM one step closer to reality. The limitations of the current design and how to overcome these in the future are discussed. Simulations show how further evolved versions of the current proof of concept might open new and exciting application prospects for beam shaping and aberration correction.