<img alt="CUED" src="/cued/branding/logo_inverted.png#gh-dark-mode-only" height="100">

<img alt="CUED" src="/cued/branding/logo.png#gh-light-mode-only" height="100">

Package for computing the density matrix dynamics in solids exposed to ultrafast light pulses implementing the Semiconductor Bloch equations (SBE). Includes computation of k-dependent bandstructures and dipole moments, computation of currents and emission intensity.

<h3>How to cite and reference CUED</h3> When using the CUED software package, please cite the following publication: <br><br> J. Wilhelm, P. Grössing, A. Seith, J. Crewse, M. Nitsch, L. Weigl, C. Schmid, and F. Evers, <i>Semiconductor-Bloch Formalism: Derivation and Application to High-Harmonic Generation from Dirac Fermions</i>, <a href="https://doi.org/10.1103/PhysRevB.103.125419">Phys. Rev. B <b>103</b>, 125419 (2021)</a>. <h3>Getting and running the code on Linux</h3>

To download the current version of the code, run

git clone https://github.com/ccmt-regensburg/CUED CUED

Change to the directory of the code:

cd CUED

Type pwd and set the outcome as pythonpath:

export PYTHONPATH=$PYTHONPATH:"/path/to/CUED"

Mandatory files for running the code are params.py containing the parameters of the calculation and the runscript runscript.py. You can find exemplary parameter files and runscripts in the directory tests and published_calculations. Now, you can run a test, for example

cd tests/01_Dirac_Nk1_2_Nk2_2_velocity/
python3 runscript.py

The code is MPI parallel, you can also run it via

mpirun -np 2 python3 runscript.py

The output is written to time_data.dat (time-dependent current) and frequency_data.dat (emission spectrum). If you set save_latex_pdf = True in params.py and if pdflatex is installed on your Linux machine, CUED will generate latex_pdf_files/CUED_summary.pdf containing plots of the bandstructure, dipoles, Brillouin zone, current, emission spectrum, ...