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Parallelized Finite Difference Time Domain (FDTD) Solver

• Version 3.0, October 04, 2021
• Author(s): Michael Strickland, Rafael L. Delgado, Sebastian Steinbeißer, Johanes H. Weber
• Email: [email protected], [email protected], [email protected], [email protected]

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DESCRIPTION

This code can use several techniques (finite differences and Fast Fourier Transform) to solve the Schrödinger Equation in imaginary time for an arbitrary 3d potential. It uses the MPI (Message Passing Interface) standard. The lattice is equally partitioned into slices along the x direction. Code can extract ground state and first few excited state wavefunction and energies.

The Relativistic Kinetic Term for the Schrodinger Equation can be used by means of the Fast Fourier Transform (FFT), with strictly periodic boundary conditions.

REQUIREMENTS

The MPI (Message Passing Interface) API must be installed on your system. Currently tested against MPICH and OpenMPI. Can run on a single computational node or as many as you like.

The FFTW3-MPI and GSL (GNU Scientific Library) are also required to be installed.

COMPILING

To compile, simply type make from the command line.

USAGE

To run:

mpirun -np <Number of Worker Nodes> mpisolve

All parameters are specified in the params.txt file. They can also be set via the commandline using, e.g.,

mpirun -np <Number of Worker Nodes> mpisolve -PARAMNAME [value]

Parameters set via the commandline override those set in the params.txt file.

DEBUGGING

mpirun N -x DISPLAY run_gdb.csh mpisolve

CONTRIBUTORS

Michael Strickland, Adrian Dumitru, Yun Guo, Rafael L. Delgado, Sebastian Steinbeißer, and Johannes H. Weber

LICENSE

GNU General Public License (GPLv3). See detailed text in the LICENSE.md file.

ATTRIBUTION

We ask that if you use this code for work which results in a publication that you cite the following papers:

Rafael L. Delgado, Sebastian Steinbeißer, Michael Strickland, and Johannes H. Weber,
"The Relativistic Schrödinger Equation through FFTW3: An Extension of quantumfdtd",
Computer Physics Communications 272 (2022), 108250.
https://inspirehep.net/literature/1804287

M. Strickland, and D. Yager-Elorriaga,
"A Parallel Algorithm for Solving the 3d Schrodinger Equation",
Journal of Computational Physics 229 (2010), 6015.
https://inspirehep.net/literature/817954