Regensburg 2022 – wissenschaftliches Programm
KFM 21.11: Vortrag
Mittwoch, 7. September 2022, 18:00–18:15, H36
Finite supercell charge correction for electronic transitions in defects including electronic and ionic screening — •Christoph Freysoldt1, Baoying Dou1, Stefano Falletta2, and Jörg Neugebauer1 — 1Max-Planck-Institut für Eisenforschung GmbH, Max-Planck-Str. 1, 40237 Düsseldorf — 2Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
Charged point defects play an important role in the function of (opto)electronic devices. Theoretical investigations have proven valuable to understand quantitatively their stability, electrical and optical properties, and hence their beneficial or detrimental role in device performance. Electronic transitions involving localized defect states have recently moved into the focus. Similar to formation energies, also the transition energies suffer from artifacts due the long-range Coulomb interactions and the artificial periodicity in supercell models of defects. While the initial charge state is subject to full electronic and ionic screening, the changes upon the transition are screened by electrons only. Yet, the required charge corrections cannot be derived by cleverly combining traditional corrections for formation energies of initial and final state. I will present an overview of how these artifacts can be understood and corrected for. I will show applications for vertical transitions and non-radiative carrier capture.