Theoretical Prediction of Atomic Vibration Modes in Core-Shell Quantum Dot Superlattices and Nanoporous Systems for the Hot Carrier Solar Cell

Phonon dispersion relations and in core-shell quantum dot superlattices and periodic arrays of gasfilled nanopores have been computed numerically in the harmonic approximation. Core-shell quantum dot superlattices show potential to inhibit first order phonon decay. Outcomes for nanoporous systems depend strongly on surface and gas-phase interactions. Surface fields in nanoporous systems have been calculated by a diffusive quantum Monte Carlo method using aspects of density functional theory. Results from these computations are presented here and implications are discussed. A light absorbing material with low probability for phonon decay is critical to achieving the high efficiencies expected from the hot carrier solar cell.