Electron fourier ptychography for phase reconstruction

TL;DR

This paper introduces a new electron microscopy technique for high-resolution phase reconstruction of materials without requiring special equipment.

Contribution

Electron Fourier ptychography is introduced as a novel method for phase reconstruction in electron microscopy.

Findings

The method achieves a spatial resolution of 0.63 nm at a fluence of 4.5 × 10² e⁻/nm².

It works effectively on Cry11Aa protein crystals under cryogenic conditions.

The technique is compatible with existing data collection software and requires no hardware changes.

Abstract

Exit wavefunction reconstruction is important in transmission electron microscopy for structural studies. We describe electron Fourier ptychography and its application to phase reconstruction of both radiation-resistant and beam-sensitive materials. We demonstrate that the phase of the exit wave can be reconstructed to high resolution using a modified iterative phase retrieval algorithm from data collected in an alternative optical geometry. This method achieves a spatial resolution of 0.63 nm at a fluence of 4.5 × 102 e−/nm2, as validated on Cry11Aa protein crystals under cryogenic conditions. Notably, this method requires no instrumental modifications, is straightforward to implement, and can be seamlessly integrated with existing data collection software, providing a broadly accessible alternative approach for structural studies.

The online version contains supplementary material available at 10.1038/s41598-025-21638-7.

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