Transforming nonlocality into a frequency dependence: a shortcut to spectroscopy.
Measurable spectra are often derived from contractions of many-body Green's functions. One calculates hence more information than needed. Here we present and illustrate an in principle exact approach to construct effective potentials and kernels for the direct calculation of electronic spectra. In particular, a dynamical but local and real potential yields the spectral function needed to describe photoemission. We discuss for model solids the frequency dependence of this "photoemission potential" stemming from the nonlocality of the corresponding self-energy.
Gatti
Matteo
M
Laboratoire des Solides Irradiés, Ecole Polytechnique, CNRS-CEA/DSM, F-91128 Palaiseau, France.
Olevano
Valerio
V
Reining
Lucia
L
Tokatly
Ilya V
IV