Published July 19, 2021
| Version v1
Dataset
Open
Synthetic 4D STEM dataset based on a SrTiO3 supercell with two additional artificial spatial frequencies
- 1. Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons, Forschungszentrum Jülich, 52425 Jülich, Germany; 2nd Institute of Physics, RWTH Aachen University, 52074 Aachen, Germany
- 2. Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons, Forschungszentrum Jülich, 52425 Jülich, Germany
Description
This dataset allows to investigate phase contrast methods for 4D scanning transmission electron microscopy, such as ptychography.
A synthetic dataset has been simulated, based on an SrTiO3 unit cell as a starting point. Then, a five by five super cell was created by repetition. Two artificial spatial frequencies were added to the phase grating, one with a wavelength of a single unit cell and one with a wavelength of the super cell. To eliminate dynamical scattering, a 4D-STEM simulation with 20 × 20 scan points per unit cell was performed using only one slice with a thickness of one unit cell along electron beam direction [001].
Files
- conf_01.mat: HDF5 file with the phase grating.
- Data extraction and plot of the phase grating.ipynb: Jupyter notebook showing how to access the phase grating file and plot the data.
- slice_00001_thick_1.9525_nm_blocksz100.raw: Simulated 4D STEM dataset as a raw binary file. Shape 100 x 100 x 596 x 596, dtype float32.
- ssb-example.ipynb: Jupyter notebook showing first moment analysis and ptychography with the dataset.
Simulation parameters
- Scan points: 100x100
- Field of view: 1.9525nm
- Convergence angle: 23mrad, 136 px
- Acceleration voltage: 300 kV
- Center: (297, 297)
- Rotation angle: 0°
Notes
Achim Strauch and Knut Müller-Caspary were supported by funding from the Initiative and Network Fund of the Helmholtz Association (Germany) under contract VH-NG-1317 (moreSTEM project).
Knut Müller-Caspary acknowledges support from Helmholtz within the project "Ptychography 4.0" under contract ZT-I-0025.
Files
Data extraction and plot of the phase grating.ipynb
Additional details
References
- Live processing of momentum-resolved STEM data for first moment imaging and ptychography. Achim Strauch, Dieter Weber, Alexander Clausen, Anastasiia Lesnichaia, Arya Bangun, Benjamin März, Feng Jiao Lyu, Qing Chen, Andreas Rosenauer, Rafal Dunin-Borkowski, Knut Müller-Caspary. arXiv:2106.13457
- Weber, Dieter, Lesnichaia, Anastasiia, Strauch, Achim, Clausen, Alexander, Bangun, Arya, Melnyk, Oleh, … Müller-Caspary, Knut. (2021, July 1). Ptychography 4.0: 0.1.0 (Version 0.1.0). Zenodo. http://doi.org/10.5281/zenodo.5055127
- Clausen, Alexander, Weber, Dieter, Ruzaeva, Karina, Migunov, Vadim, Baburajan, Anand, Bahuleyan, Abijith, … Dunin-Borkowski, Rafal E. (2021, July 8). LiberTEM/LiberTEM: 0.7.1 (Version 0.7.1). Zenodo. http://doi.org/10.5281/zenodo.5083032