Optoelectronic excitations and photovoltaic effect in strongly correlated materials

Abstract

Solar cells based on conventional semiconductors have low efficiency in converting solar energy into electricity because the excess energy beyond the gap of an incident solar photon is converted into heat by phonons. Here we show by ab initio methods that the presence of strong Coulomb interactions in strongly correlated insulators (SCI) causes the highly photo-excited electron-hole pair to decay fast into multiple electron-hole pairs via impact ionization (II). We show that the II rate in the insulating $M_1$ phase of vanadium dioxide (chosen for this study as it is considered a prototypical SCI) is two orders of magnitude higher than in Si and much higher than the rate of hot electron/hole decay due to phonons. Our results indicate that a rather broad class of materials may be harnessed for an efficient solar-to-electrical energy conversion that has been not considered before.

arXiv comment5 Latex pages, 3 figures, and also supplementary material

References in corpus (14)

• High Efficiency Carrier Multiplication in PbSe Nanocrystals: Implications for Solar Energy
• Quasiparticle Self-Consistent GW Theory
• Electrodynamics of the vanadium oxides VO2 and V2O3
• Vanadium dioxide : A Peierls-Mott insulator stable against disorder
• Predictive GW calculations using plane waves and pseudopotentials
• Carrier multiplication between interacting nanocrystals for fostering silicon-based photovoltaics
• Optical properties of correlated materials -- Generalized Peierls approach and its application to VO2
• GW method applied to localized 4f electron systems
• Role of electron-electron and electron-phonon interaction effect in the optical conductivity of VO2
• Correlation Assisted Phonon Softenings and the Mott-Peierls Transition in VO${}_2$
• Photovoltaic effect for narrow-gap Mott insulators
• Many-body Electronic Structure of Metallic alpha-Uranium
• GaN / VO2 heteroepitaxial p-n junctions: Band offset and minority carrier dynamics
• Impact ionization rates for Si, GaAs, InAs, ZnS, and GaN in the $GW$ approximation

Cited by in corpus (10)

• Convergence of quasiparticle self-consistent GW calculations of transition metal monoxides
• Photo-induced nonequilibrium states in Mott insulators
• Impact ionization processes in the steady state of a driven Mott insulating layer coupled to metallic leads
• Impact ionization processes in a photodriven Mott insulator: influence of phononic dissipation
• Many-body recombination in insulating cuprates
• Impact ionization and multiple photon absorptions in the two-dimensional photoexcited Hubbard model
• Multiple exciton generation in VO2
• Photodriven Mott insulating heterostructures: A steady-state study of impact ionization processes
• Growth and Characterization of Off-Stoichiometric LaVO${}_3$ Thin Films
• Excitonic-trion population in two-dimensional halide perovskites