On the effect of precession for magnetic differential phase contrast imaging

4D-STEM datasets and processing scripts used for the journal publication "On the effect of precession for magnetic differential phase contrast imaging".

DOI link to publication: 10.1016/j.micron.2024.103761

Prerequisites

The scripts presented below were created using open-source Python packages with specific versions:

• hyperspy 1.7.1
• pyxem 0.14.2
• fpd 0.2.5 (with scikit-image 0.18)
• jupyterlab 4.0.7

There is no guarantee that other versions of the listed packages will run the code.

Data files

In total five zipped (.7z extension) files are included in this repository. The files contain data from the different samples studied with different precession electron diffraction calibrations where applicable. The three samples studied are LSMO, and the corresponding 4D-STEM datasets taken away from a high-symmetry zone axis (LSMO_LZ_data.7z) and on the zone axis (LSMO_HZ_data.7z), FeAl sample (FeAl_data.7z), and scans from an Au TEM alignment grid (AuGrid_data.7z). The precession_azimuths.7z files contains the precession azimuthal circles from the three precession calibrations performed.

Processing scripts

Three scripts are included in the IPython notebook format (.ipynb extension). The Precession_azimuth_plot.ipynb script plots the precession azimuth for comparison. The Segmentation_script.ipynb is used to process the precession path segmented 4D-STEM datasets, and the DPC_processing.ipynb includes code to perform center of mass and phase correlation processing on the 4D-STEM data to extract differential phase contrast signals.