kdotpy is a Python application for simulating electronic band structures of semiconductor devices with k·p theory on a lattice.

Installation

You can install kdotpy using PIP, from the Python Package Index (PyPI):

python -m pip install kdotpy

Alternatively, you can download the source and install it from your local copy:

git clone https://git.physik.uni-wuerzburg.de/kdotpy/kdotpy.git
python -m pip install ./kdotpy

For an editable install for active coding and debugging, add the -e option to pip install, like so: python -m pip install -e ./kdotpy.

Usage

kdotpy is designed as a standalone application with a command line interface. If you have followed the installation instructions above, you can simply run kdotpy from the command line, followed by the 'sub-programme' label and further arguments. You can do this from any folder.

The first argument is always the sub-programme. The calculation scripts are kdotpy 1d, kdotpy 2d, kdotpy bulk, kdotpy ll, and kdotpy bulk-ll. There are two re-plot scripts, kdotpy merge and kdotpy compare. Batch calculations can be done with kdotpy batch. The scripts kdotpy config, kdotpy help, and kdotpy doc give access to configuration and information. Finally, kdotpy test runs pre-defined tests for checking that kdotpy works correctly.

You can also use python -m kdotpy followed by the sub-programme and further arguments.

Example

kdotpy 2d 8o noax msubst CdZnTe 4% mlayer HgCdTe 68% HgTe HgCdTe 68% llayer 10 7 10 zres 0.25 k -0.6 0.6 / 60 kphi 45 erange -80 0 split 0.01 obs orbitalrgb legend char out -7nm outdir data-qw localminmax

This and more examples can be found in the Tutorials section of the Wiki: https://git.physik.uni-wuerzburg.de/kdotpy/kdotpy/-/wikis/tutorials/overview

More information

Repository: https://git.physik.uni-wuerzburg.de/kdotpy/kdotpy

Wiki: https://git.physik.uni-wuerzburg.de/kdotpy/kdotpy/-/wikis/home

Website: https://kdotpy.physik.uni-wuerzburg.de

Article: https://doi.org/10.21468/SciPostPhysCodeb.47

Authors

The following people are members of the kdotpy collaboration.

Maintainers and developers:

• Wouter Beugeling
• Florian Bayer
• Christian Berger
• Maximilian Hofer
• Julian Kuther

Other contributors:

• Jan Böttcher
• Leonid Bovkun
• Christopher Fuchs
• Saquib Shamim
• Moritz Siebert
• Li-Xian Wang
• Ewelina M. Hankiewicz
• Tobias Kießling
• Hartmut Buhmann
• Laurens W. Molenkamp

We thank Domenico Di Sante, Giorgio Sangiovanni, Björn Trauzettel, Florian Goth, and Fakher Assaad for feedback and support at various stages of the project.

We acknowledge financial support from the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) in the project SFB 1170 ToCoTronics and in the Würzburg-Dresden Cluster of Excellence on Complexity and Topology in Quantum Matter ct.qmat (EXC 2147), and from the Free State of Bavaria for the Institute for Topological Insulators.

Crediting us

If you use kdotpy, we encourage you to credit our work as you would do with any scientific work. Please cite us as follows:

W. Beugeling, F. Bayer, C. Berger, J. Böttcher, L. Bovkun, C. Fuchs, M. Hofer, S. Shamim, M. Siebert, L.-X. Wang, E. M. Hankiewicz, T. Kießling, H. Buhmann, and L. W. Molenkamp, "kdotpy: k·p theory on a lattice for simulating semiconductor band structures", SciPost Phys. Codebases 47 (2025).

The DOI for this work is 10.21468/SciPostPhysCodeb.47.

We also encourage you to show the kdotpy logo with graphics you present, for example in oral presentations and on posters.

For detailed instructions, please refer to the document CITATION.md in the repository.

Contributing

We encourage interaction (bug reports, suggestions, etc.) via the issue tracker of the repository: https://git.physik.uni-wuerzburg.de/kdotpy/kdotpy/-/issues

We can also be reached by e-mail at kdotpy@uni-wuerzburg.de.

Becoming a contributor

For bug reports, suggestions, and criticisms just let us know via the issue tracker or by e-mail.

We're also looking for enthusiastic people who want to join our Developer Team. If you're interested in joining, please don't hesitate to let us know.

For information on what we expect from contributors, please note the terms stated in CONTRIBUTING.md in the repository.

License

kdotpy is licensed under the GNU General Public License, version 3.

Copyright (C) 2024-2026 The kdotpy collaboration

kdotpy is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 3.

kdotpy is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with kdotpy. If not, see https://www.gnu.org/licenses/.

A copy of the GNU General Public License is included as the file LICENSE in the kdotpy repository. Additional terms under Section 7 of the GNU General Public License, version 3, are stated in the file LICENSE.additional.

Contact

e-mail: kdotpy@uni-wuerzburg.de

website: https://kdotpy.physik.uni-wuerzburg.de

Git repository: https://git.physik.uni-wuerzburg.de/kdotpy/kdotpy