Hund excitations and the efficiency of Mott solar cells

Abstract

We study the dynamics of photo-induced charge carriers in realistic models of LaVO3 and YTiO3 polar heterostructures. It is shown that two types of impact ionization processes contribute to the carrier multiplication in these strongly correlated multi-orbital systems: The first mechanism involves local spin state transitions, while the second mechanism involves the scattering of high kinetic energy carriers. Both processes act on the 10 fs timescale and play an important role in the harvesting of high energy photons in solar cell applications. As a consequence, the optimal gap size for Mott solar cells is substantially smaller than for semiconductor devices.

arXiv comment7 pages, 6 figures

References in corpus (19)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Wannier90: A Tool for Obtaining Maximally-Localised Wannier Functions
• Maximally localized Wannier functions: Theory and applications
• Nonequilibrium dynamical mean-field theory and its applications
• Janus-faced influence of the Hund's rule coupling in strongly correlated materials
• Nonequilibrium dynamical mean-field calculations based on the non-crossing approximation and its generalizations
• Dielectric breakdown of Mott insulators in dynamical mean-field theory
• Oxide Heterostructures for Efficient Solar Cells
• Ultrafast doublon dynamics in photo-excited 1T-TaS${}_2$
• Orbital fluctuations in the different phases of LaVO3 and YVO3
• Role of impact ionization in the thermalization of photo-excited Mott insulators
• Photovoltaic effect for narrow-gap Mott insulators
• Ultrafast separation of photo-doped carriers in Mott antiferromagnets
• Consequences of local gauge symmetry in empirical tight-binding theory
• Nonequilibrium dynamical mean field simulation of inhomogeneous systems
• Dynamics of photo-doped charge transfer insulators
• Structural and electronic properties of epitaxially-strained LaVO_3 from density functional theory and dynamical mean-field theory
• Ultrafast switching of composite order in A${}_3$C${}_{60}$
• Pressure-driven orbital reorientation and change in Mott-Hubbard gap in YTiO3

Cited by in corpus (16)

• Gauge invariance of light-matter interactions in first-principle tight-binding models
• Photo-induced nonequilibrium states in Mott insulators
• Enhancement of impact ionization in Hubbard clusters by disorder and next-nearest-neighbor hopping
• Photo-induced charge dynamics in 1$T$-TaS${}_2$
• Time-dependent ghost-Gutzwiller non-equilibrium dynamics
• Causal versus local $GW$+EDMFT scheme and application to the triangular-lattice extended Hubbard model
• Impact ionization processes in a photodriven Mott insulator: influence of phononic dissipation
• Impact ionization and multiple photon absorptions in the two-dimensional photoexcited Hubbard model
• Nature of the photo-induced metallic state in monoclinic VO${}_2$
• Local interpretation of time-resolved X-ray absorption in Mott insulators: Insights from nonequilibrium dynamical mean-field theory
• Hund bands in spectra of multiorbital systems
• Photo-induced insulator-metal transition in paramagnetic (V${}_{1-x}$Cr${}_x$)${}_2$O${}_3$
• Multiple exciton generation in VO2
• A new pathway to impact ionization in a photo-excited one-dimensional ionic Hubbard model
• Photodriven Mott insulating heterostructures: A steady-state study of impact ionization processes
• Nonequilibrium-DMFT based RIXS investigation of the two-orbital Hubbard model