METHES: Montecarlo ETH Electron Scattering code for electron transport in electric fields

METHES is a Monte-Carlo collision code written in MATLAB for the simulation of electron transport in arbitrary gas mixtures in the presence of electric fields. For steady-state electron transport in a uniform electric field, the program provides the transport coefficients, reaction rates and the electron energy distribution function. The program is compatible with the electron scattering cross section files from LXCat in order to enable direct comparison with the results of BOLSIG+. Temporal studies of electron transport are possible by tracking position, velocity and number of electrons.

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
Proper reference is made in publications reporting results obtained using this software. At present, the preferred way to reference METHES is as follows:

M. Rabie and C.M. Franck, "METHES: A Monte Carlo collision code for the simulation of electron transport in low temperature plasmas, Comput. Phys. Comm., 203 (2016), pp. 268-277 as well as M. Rabie and C.M. Franck, METHES code, downloaded from www.lxcat.net/download/METHES, 2015.

main features

Monte Carlo Code written in object-orientated design in MATLAB environment
Compatible with the electron scattering cross section text files from LXCat
Steady-state electron transport in a uniform electric field: transport parameters, electron energy distribution and reaction rates
Temporal studies of electron transport possible by tracking position, velocity and number of electrons
For the experienced user: inhomogeneous electric field calculations possible

download METHES package for MATLAB

Update 1st July 2015: maximum collision frequency is automatically minimized during the simulation.
Update 19th March 2015: first public version.

contact authors

Mohamed Rabie (rm@ethz.ch) and Christian Franck (cfranck@ethz.ch)

Define simulation parameters

Gas species
Mixing ratio
Reduced field E/N in Townsend
Computationally fix (or not fix) electron number
Isotropic or non-isotropic scattering
Numerical settings: electron number, energy sharing factor, energy increment

Import and view cross sections

Cross section sets in the format of the LXCat text files are needed
Effective cross sections are possible input instead of elastic cross sections

Perform simulation and view temporal development

Mean energy and electron energy distribution (EEDF) and probability function (EEPF)
Swarm position
Swarm width
Electron number
Electron positions

Extract and save swarm parameters

When steady state is reached (SST), a view temporal swarm parameters are shown in workspace (saved in the file temporal.txt). The complete swarm parameters are saved in the file results.mat.
Mean energy and EEDF and EEPF
Flux transport data
Bulk transport data
Reaction rates

Acknowledgments

We thank S. Dujko for valuable discussions. This work is financially supported by ALSTOM Grid AG (Switzerland), Pfiffner AG and ABB Switzerland.