Simulated calibration dataset for 4D scanning transmission electron microscopy

4D-STEM data frequently requires a number of calibrations in order to make accurate measurement: for instance, in various cases, it can be essential to measure and correct for diffraction shifts, account for ellipticity in the diffraction patterns, or determine the rotational offset between the real and diffraction planes.

We've prepared a simulated 4D-STEM dataset which includes diffraction shifting, elliptical distortion, and an r-space/k-space rotational offset.  Two HDF5 files each include the simulated data for two different electron probes: a standard probe, using a circular probe-forming aperture, and a 'bullseye' probe, using a patterned aperture.  Each HDF5 file contains the following data objects:

(a) the 'experimental' 4D-STEM scan of a strained single-crystal gold nanoparticle (size: (100,84,250,250) )

(b) a 4D-STEM scan of a calibration sample of polycrystalline gold (size: (100,84,250,250) )

(c) a stack of diffraction images of the electron probe over vacuum (size: (250,250,20) )

(d) a single image of the electron probe over the sample and far from focus, such that the CBED forms a shadow image (size: (512,512) )