Speeding up GW Calculations to Meet the Challenge of Large Scale Quasiparticle Predictions

Accurate quasiparticle spectra from self-consistent GW calculations with vertex corrections.

Self-consistent GW calculations, maintaining only the quasiparticle part of the Green's function G, are reported for a wide class of materials, including small gap semiconductors and large gap insulators. We show that the inclusion of the attractive electron-hole interaction via an effective nonlocal exchange correlation kernel is required to obtain accurate band gaps in the framework of self-c...

Simple approximate physical orbitals for GW quasiparticle calculations.

Generating unoccupied orbitals within density functional theory (DFT) for use in GW calculations of quasiparticle energies becomes prohibitive for large systems. We show that, without any loss of accuracy, the unoccupied orbitals may be replaced by a set of simple approximate physical orbitals made from appropriately prepared plane waves and localized basis DFT orbitals that represent the conti...

Quasiparticle lifetimes in magnesium clusters modeled by self-consistent GW calculations

Quasiparticle Calculations for Point Defects on Semiconductor Surfaces

We discuss the implementation of quasiparticle calculations for point defects on semiconductor surfaces and, as a specific example, present an ab initio study of the electronic structure of the As vacancy in the +1 charge state on the GaAs(110) surface. The structural properties are calculated with the plane-wave pseudopotential method, and the quasiparticle energies are obtained from Hedin’s G...

Electronic structure of Pu and Am metals by self-consistent relativistic GW method

We present the results of calculations for Pu and Am performed using an implementation of a self-consistent fully relativistic GW method. The key feature of our scheme is to evaluate polarizability and self-energy in real space and Matsubara’s time. We compare our GW results with the calculations using local density and quasiparticle approximations and also with scalar-relativistic calculations...