UppASD

Uppsala Atomistic Spin Dynamics software

The UppASD software package is a simulation suite to study magnetization dynamics by means of the atomistic version of the Landau-Lifshitz-Gilbert (LLG) equation.

Applications:

• Critical temperature determination
• Magnon spectra simulations
• Micromagnetic exchange and DMI stiffness calculations
• Current, field, and temperature-driven dynamics

Features:

• LLG, Metropolis, and Heat-bath algorithms
• Generalized Hamiltonian including
  • bilinear and biquadratic Heisenberg exchange
  • Dzyaloshinskii-Moriya exchange
  • magnetocrystalline anisotropies.
• Support for arbitrary crystal structures and random alloys
• Spin-transfer and spin-orbit torques
• Temperature gradients
• Quantum statistics

Detailed information about the method can be found in
Atomistic Spin Dynamics: Foundations and Applications
O. Eriksson et. al, Oxford University Press 2017

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Quick-start:

./setup_UppASD.sh   
make <profile>

Where <profile> is a suitable compiler profile, i.e. ifort, gfortran, gfortran-osx, gfortran-ftn, aocc-ftn and so on.

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Quick-start alternative (using cmake):

cmake -S . -B build   
cmake --build build

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The binary is compiled to the ./bin/ directory.

Examples are provided in ./examples/

The code is documented in the UppASD manual.

A tutorial with examples and exercises on atomistic spin-dynamics are contained in the UppASD tutorial.

Developers please look at the development guidelines in the CONTRIBUTING.md file, about how to make your contributions to UppASD.

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Graphical User Interface

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A python based QT GUI for the code is also available at ./ASD_GUI/ASD_GUI.py. This allows for:

• Visualization of outputs via VTK.
• Plotting of several quantities via integrated matplotlib functionalities.
• Automatic generation of input files for UppASD.

Requirements

• Qt6.
• python3.6 or higher.
  • pandas
  • numpy
  • PyYaml
  • matplotlib
• VTK8.0 or higher.

Installation Guide (pip)

The recommended way to install the prerequisites for the ASD_GUI is currently to use pip and virtualenv environments.

After installing virtualenv one can create virtual environment where to host the ASD_GUI. This can be done in the following way:

pip install virtualenv
virtualenv ASD_GUI_env 
source ASD_GUI_env/bin/activate
pip install numpy matplotlib pyyaml pandas pyqt6 vtk

This will generate a virtual environment named ASD_GUI_env which can be activated or deactivated to run the GUI. The following steps are also recommended (starting from the base directory of the repo):

cd ASD_GUI
pip install .

This will install the GUI as a proper Python module and you can then start the GUI from any point in your file system by issuing the asd_gui command at the command prompt.

Installation Guide (anaconda)

An alternative way to install the prerequisites for the ASD_GUI can be done via the anaconda framework and its environments.

After installing anaconda one can create virtual environment where to host the ASD_GUI. This can be done in the following way:

conda create --name ASD_GUI_env python vtk numpy scipy matplotlib yaml pyyaml pandas pyqt
source activate ASD_GUI_env

This will generate a conda environment named ASD_GUI_env which can be activated or deactivated to run the GUI.

Note: The anaconda approach might not work untill the conda repositories update pyqt to support Qt6.

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(C) 2008-2023 UppASD group