Scientific Achievement
Researchers in the Theory of Materials Program demonstrated that the effects of finite temperatures, commonly ignored in ab initio calculations of excitons in solids, can reduce their binding energies by up to 70% at room temperature and drive ultra-fast dissociation towards free charges following photoexcitation.
Significance and Impact
Since solar cells and LEDs generally operate at room temperature a rigorous incorporation of temperature in ab initio approaches of optoelectronic materials is critical for discovery, understanding and design.
Research Details
- Extended the ab initio GW-Bethe Salpeter equation framework to include phonon effects on excitons and exciton dissociation at finite temperatures
- Developed efficient computational framework and predicted temperature-dependent excitonic properties of diverse semiconductors
Publication Details
A.M. Alvertis, J.B. Haber, Z.-L. Li, C.J.N. Coveney, S.G. Louie, M. R. Filip, J.B. Neaton, PNAS (2024).
Work was performed in part at the NERSC.
