Photo-enhanced excitonic correlations in a Mott insulator with nonlocal interactions

Abstract

We investigate the effect of nonlocal interactions on the photo-doped Mott insulating state of the two-dimensional Hubbard model using a nonequilibrium generalization of the dynamical cluster approximation. In particular, we compare the situation where the excitonic states are lying within the continuum of doublon-holon excitations to a set-up where the excitons appear within the Mott gap. In the first case, the creation of nearest-neighbor doublon-holon pairs by excitations across the Mott gap results in enhanced excitonic correlations, but these excitons quickly decay into uncorrelated doublons and holons. In the second case, photo-excitation results in long-lived excitonic states. While in a low-temperature equilibrium state, excitonic features are usually not evident in single-particle observables such as the photoemission spectrum, we show that the photo-excited nonequilibrium system can exhibit in-gap states associated with the excitons. The comparison with exact-diagonalization results for small clusters allows us to identify the signatures of the excitons in the photo-emission spectrum.

References in corpus (12)

• Screened Coulomb interaction in the maximally localized Wannier basis
• Theoretical description of time-resolved photoemission spectroscopy: application to pump-probe experiments
• Excitons versus electron-hole plasma in monolayer transition metal dichalcogenide semiconductors
• Screening and Non-local Correlations in the Extended Hubbard Model from Self-Consistent Combined GW and Dynamical Mean Field Theory
• Local Order and the gapped phase of the Hubbard model: a plaquette dynamical mean field investigation
• Intervalley scattering in MoS${}_2$ imaged by two-photon photoemission with a high-harmonic probe
• Witnessing the formation and relaxation of massive quasi-particles in a strongly correlated electron system
• Field-induced polaron formation in the Holstein-Hubbard model
• Role of impact ionization in the thermalization of photo-excited Mott insulators
• Optical conductivity in cluster dynamical mean field theory: formalism and application to high temperature superconductors
• Photoinduced in-gap excitations in the one-dimensional extended Hubbard model
• Photoinduced absorptions inside the Mott gap in the two-dimensional extended Hubbard model

Cited by in corpus (14)

• Photo-induced nonequilibrium states in Mott insulators
• Nonequilibrium dynamics in pumped Mott insulators
• Nonequilibrium Two-Particle Self-Consistent Approach
• Nonequilibrium dynamics of $\alpha$-RuCl${}_3$ -- a time-resolved magneto-optical spectroscopy study
• In-Gap Band Formation in a Periodically Driven Charge Density Wave Insulator
• Spin correlations in the bilayer Hubbard model with perpendicular electric field
• Measuring the ultrafast screening of $U$ in photo-excited charge-transfer insulators with time-resolved X-ray absorption spectroscopy
• Exciton-spin interactions in antiferromagnetic charge-transfer insulators
• Third-order strong-coupling impurity solver for real-frequency DMFT: Accurate spectral functions for antiferromagnetic and photo-doped states
• From strong to weak correlations in breathing-mode kagome van der Waals materials: Nb${}_3$(F,Cl,Br,I)${}_8$ as a robust and versatile platform for many-body engineering
• Photoemission Signatures of Photoinduced Carriers and Excitons in One-Dimensional Mott Insulators
• Quantitative determination of the orbital-selective Mott transition and quantum entanglement in the orbital-selective Mott phase
• Interaction effects on electronic Floquet spectra: Excitonic effects
• Photoinduced excitonic magnetism in a multiorbital Hubbard system