BerkeleyGW

Website: berkeleygw.org

BerkeleyGW is a many-body perturbation theory code for excited states, using the GW method and the GW plus Bethe-Salpeter equation (GW-BSE) method to solve respectively for quasiparticle excitations and optical properties of materials. BerkeleyGW is:

• Suitable for 3D, 2D, 1D, and molecular systems;
• Applicable to insulating, metallic, and semi-metallic systems;
• Massively parallelized with MPI, OpenMP, SIMD;
• Recently ported to GPUs, reaching 86x speedup compared to the CPU implementation.

The latest BerkeleyGW can be applied to study multi-thousand-atom systems. A recent calculation of GW quasiparticle excitation energies of divacancies in Si and SiC adopts a supercell contains > 2700 atoms (> 10,000 electrons), reaching 105.9 double-precision PetaFLOP/s, 52.7% of the peak performance, running at full-scale of Summit at OLCF with 27,648 GPUs.

The BerkeleyGW package takes mean-field solutions (for example, DFT wavefunctions and eigenvalues) as input for the many-body perturbation theory calculations. BerkeleyGW currently is interfaced with the following DFT codes with efficient built-in wrappers:

• Abinit
• Octopus
• PARATEC
• PARSEC
• Quantum ESPRESSO
• RMGDFT
• SIESTA
• TBPW

The package consists of the three main component codes:

• Epsilon computes the irreducible polarizability in the Random Phase Approximation and uses it to generate the dielectric matrix and its inverse.

• Sigma computes the self-energy corrections to the DFT eigenenergies using the GW approximation of Hedin and Lundqvist, applying the first-principles methodology of Hybertsen and Louie within the generalized plasmon-pole model for the frequency-dependent dielectric matrix.

• BSE solves the Bethe-Salpeter equation for correlated electron-hole excitations.

As a condition for using BerkeleyGW, you are asked to cite the following papers and acknowledge the use of the BerkeleyGW package in your publications.

• [1] Mark S. Hybertsen and Steven G. Louie, “Electron correlation in semiconductors and insulators: Band gaps and quasiparticle energies,” Phys. Rev. B 34, 5390 (1986)

• [2] Michael Rohlfing and Steven G. Louie, “Electron-hole excitations and optical spectra from first principles,” Phys. Rev. B 62, 4927 (2000)

• [3] Jack Deslippe, Georgy Samsonidze, David A. Strubbe, Manish Jain, Marvin L. Cohen, and Steven G. Louie, “BerkeleyGW: A Massively Parallel Computer Package for the Calculation of the Quasiparticle and Optical Properties of Materials and Nanostructures,” Comput. Phys. Commun. 183, 1269 (2012) (http://arxiv.org/abs/1111.4429)

Papers [1] and [3] should be cited when discussing quasiparticle properties such as GW band structures, and papers [2] and [3] should be cited when discussing optical properties with excitonic effects.