Accurate energy bands calculated by the hybrid quasiparticle self-consistent GW method implemented in the ecalj package

Abstract: We have recently implemented a new version of the quasiparticle self-consistent GW (QSGW) method in the ecalj package released at http://github.com/tkotani/ecalj. Since the new version of the ecalj is numerically stable and accurate compared to the previous versions, we can perform calculations easily without being bothered with setting input parameters. Here we examine its ability to describe energy band properties, e.g., band-gap energy, eigenvalues at special points and effective mass, for variety of semiconductors and insulators. We treat C, Si, Ge, Sn, SiC (in 2H, 3C, and 4H structures), (Al, Ga, N)x(N, P, As, Pb), (Zn, Cd, Mg)x(O, S, Se, Te), SiO2, HfO2, ZrO2, SrTiO3, PbS, PbTe, MnO, NiO, and HgO. We propose that a hybrid QSGW method, where we mix 80 percent of QSGW and 20 percent of LDA, gives universally good agreement with experiments for these materials.