https://doi.org/10.1140/epjb/e2010-10033-1
Optical absorption spectra of finite systems from a conserving Bethe-Salpeter equation approach
1
Physikalisch-Technische Bundesanstalt (PTB), Bundesallee 100, 38116 Braunschweig, Germany
2
Institut für Physik, Martin-Luther-University, Halle-Wittenberg, Heinrich-Damerow-Strasse 4, 06120 Halle, Germany
3
Physics Department and Research Center OPTIMAS, University of Kaiserslautern, P.O. Box 3049, 67653 Kaiserslautern, Germany
Corresponding authors: a palgeorge79@googlemail.com - b hcsch@physik.uni-kl.de
Received:
24
November
2010
Published online:
14
January
2011
We present a method for computing optical absorption spectra
by means of a Bethe-Salpeter equation approach, which is based on a
conserving linear response calculation for electron-hole coherences
in the presence of an external electromagnetic field. This procedure
allows, in principle, for the determination of the electron-hole
correlation function self-consistently with the corresponding
single-particle Green function. We analyze the general approach
for a “one-shot” calculation of the photoabsorption cross section
of finite systems, and discuss the importance of scattering and
dephasing contributions in this approach. We apply the
method to the closed-shell clusters Na4, Na
and
Na
, treating one active electron per Na atom.
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2011
