  We have developed the quasiparticle self-consistent GW (QSGW) method based on
a recently developed mixed basis all-electron full-potential method (the PMT
method), which uses the augmented plane waves (APWs) and the highly localized
muffin-tin orbitals (MTOs) simultaneously. We call this PMT-QSGW. Because of
the two kinds of augmented bases, we have efficient description of one-particle
eigenfunctions in materials with small number of basis functions. In QSGW, we
have to treat a static non-local exchange-correlation potential, which is
generated from the self-energy. We expand the potential in the highly localized
MTOs. This allows us to make stable interpolation of the self-energy in the
whole Brillouin zone. In addition, we have improved the offset-{\Gamma} method
for the Brillouin zone integration, so that we take into account the anisotropy
of the screened Coulomb interaction in the calculation of the self-energy. For
GaAs and cubic SiO2 , we checked convergence of calculated band gaps on cutoff
parameters. PMT-QSGW is implemented in a first-principles electronic structure
package ecalj, which is freely available from github.
