Beyond the Tamm-Dancoff approximation for extended systems using exact diagonalization

@inproceedings{Sander2015BeyondTT,
  title={Beyond the Tamm-Dancoff approximation for extended systems using exact diagonalization},
  author={Tobias Sander and Emanuele Maggio and Georg Kresse},
  year={2015}
}
Linear optical properties can be accurately calculated using the Bethe-Salpeter equation. After introducing a suitable product basis for the electron-hole pairs, the Bethe-Salpeter equation is usually recast into a complex non-Hermitian eigenvalue problem that is difficult to solve using standard eigenvalue solvers. In solid-state physics, it is therefore common practice to neglect the problematic coupling between the positive- and negative-frequency branches, reducing the problem to a… CONTINUE READING