1301.4273 (Anamitra Mukherjee et al.)

A variational approach for calculating Auger electron spectra: going
beyond the impurity approximation    [PDF]

Anamitra Mukherjee, George A. Sawatzky, Mona Berciu

We propose a novel variational method to calculate the two-hole propagators relevant for Auger spectroscopy, which can be thought of as an intermediary step between the full solution (which is difficult to generalize to systems with partially filled bands) and the impurity approximation. Like the former, our solution has the full translational invariance, and like the latter, it can be generalized to systems with partially filled bands. Here, we compare both our variational approximation and the impurity approximation against the exact solution for a simple one-dimensional model with filled bands, and show that when both are valid, the variational approximation is superior.

View original: http://arxiv.org/abs/1301.4273