---
res:
bibo_abstract:
- We present an implementation of the GW approximation for the electronic self-energy
within the full-potential linearized augmented-plane-wave (FLAPW) method. The
algorithm uses an all-electron mixed product basis for the representation of response
matrices and related quantities. This basis is derived from the FLAPW basis and
is exact for wave-function products. The correlation part of the self-energy is
calculated on the imaginary-frequency axis with a subsequent analytic continuation
to the real axis. As an alternative we can perform the frequency convolution of
the Green function G and the dynamically screened Coulomb interaction W explicitly
by a contour integration. The singularity of the bare and screened interaction
potentials gives rise to a numerically important self-energy contribution, which
we treat analytically to achieve good convergence with respect to the k-point
sampling. As numerical realizations of the GW approximation typically suffer from
the high computational expense required for the evaluation of the nonlocal and
frequency-dependent self-energy, we demonstrate how the algorithm can be made
very efficient by exploiting spatial and time-reversal symmetry as well as by
applying an optimization of the mixed product basis that retains only the numerically
important contributions of the electron-electron interaction. This optimization
step reduces the basis size without compromising the accuracy and accelerates
the code considerably. Furthermore, we demonstrate that one can employ an extrapolar
approximation for high-lying states to reduce the number of empty states that
must be taken into account explicitly in the construction of the polarization
function and the self-energy. We show convergence tests, CPU timings, and results
for prototype semiconductors and insulators as well as ferromagnetic nickel.@eng
bibo_authorlist:
- foaf_Person:
foaf_givenName: Christoph
foaf_name: Friedrich, Christoph
foaf_surname: Friedrich
- foaf_Person:
foaf_givenName: Stefan
foaf_name: Blügel, Stefan
foaf_surname: Blügel
- foaf_Person:
foaf_givenName: Arno
foaf_name: Schindlmayr, Arno
foaf_surname: Schindlmayr
foaf_workInfoHomepage: http://www.librecat.org/personId=458
orcid: 0000-0002-4855-071X
bibo_doi: 10.1103/PhysRevB.81.125102
bibo_issue: '12'
bibo_volume: 81
dct_date: 2010^xs_gYear
dct_identifier:
- UT:000276248900039
dct_isPartOf:
- http://id.crossref.org/issn/1098-0121
- http://id.crossref.org/issn/1550-235X
dct_language: eng
dct_publisher: American Physical Society@
dct_title: Efficient implementation of the GW approximation within the all-electron
FLAPW method@
...