Program title: EPW
Catalogue identifier: AEHA_v1_0
Program summary URL: http://cpc.cs.qub.ac.uk/summaries/AEHA_v1_0.html
Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland
Licensing provisions: GNU Public License
No. of lines in distributed program, including test data, etc.: 304 443
No. of bytes in distributed program, including test data, etc.: 1 487 466
Distribution format: tar.gz
Programming language: Fortran 90
Computer: Any architecture with a Fortran 90 compiler
Operating system: Any environment with a Fortran 90 compiler
Has the code been vectorized or parallelized?: Yes, optimized for 1 to 64 processors
RAM: Heavily system dependent, as small as a few MB
Supplementary material: A copy of the x201c;EPW/examplesx201d; directory containing the phonon binary files can be downloaded
Classification: 7
External routines: MPI, Quantum-ESPRESSO package [1], BLAS, LAPACK, FFTW. (The necessary Blas, Lapack and FFTW routines are included in the Quantum-ESPRESSO package [1].)
Nature of problem: The calculation of the electronx2013;phonon coupling from first-principles requires a very accurate sampling of electronx2013;phonon scattering processes throughout the Brillouin zone; hence reliable calculations can be prohibitively timeconsuming.
Solution method: EPW makes use of a real-space formulation and combines the Kohnx2013;Sham electronic eigenstates and the vibrational eigenmodes provided by the Quantum-ESPRESSO package with the maximally localized Wannier functions provided by the wannier90 package in order to generate electronx2013;phonon matrix elements on arbitrarily dense Brillouin zone grids using a generalized Fourier interpolation.
Running time: Single processor examples typically take 5x2013;10 minutes.
References:
[1] P. Giannozzi, et al., J. Phys. Condens. Matter 21 (2009), 395502, http://www.quantum-espresso.org/.