Exciton-exciton interactions in van der Waals heterobilayers

Abstract

Exciton-exciton interactions are key to understanding non-linear optical and transport phenomena in van der Waals heterobilayers, which emerged as versatile platforms to study correlated electronic states. We present a combined theory-experiment study of excitonic many-body effects based on first-principle band structures and Coulomb interaction matrix elements. Key to our approach is the explicit treatment of the fermionic substructure of excitons and dynamical screening effects for density-induced energy renormalization and dissipation. We demonstrate that dipolar blue shifts are almost perfectly compensated by many-body effects, mainly by screening-induced self-energy corrections. Moreover, we identify a crossover between attractive and repulsive behavior at elevated exciton densities. Theoretical findings are supported by experimental studies of spectrally-narrow interlayer excitons in atomically-reconstructed, hBN-encapsulated MoSe${}_2$/WSe${}_2$ heterobilayers. Both theory and experiment show energy renormalization on a scale of a few meV even for high injection densities in the vicinity of the Mott transition. Our results revise the established picture of dipolar repulsion dominating exciton-exciton interactions in van der Waals heterostructures and open up opportunities for their external design.

References in corpus (43)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Advanced capabilities for materials modelling with Quantum ESPRESSO
• The PseudoDojo: Training and grading a 85 element optimized norm-conserving pseudopotential table
• Observation of Long-Lived Interlayer Excitons in Monolayer MoSe2-WSe2 Heterostructures
• Strong interlayer coupling in van der Waals heterostructures built from single-layer chalcogenides
• Excitonic linewidth approaching the homogeneous limit in MoS2 based van der Waals heterostructures : accessing spin-valley dynamics
• Excitonic linewidth and coherence lifetime in monolayer transition metal dichalcogenides
• Electrical control of interlayer exciton dynamics in atomically thin heterostructures
• Long-lived direct and indirect interlayer excitons in van der Waals heterostructures
• Exciton-exciton annihilation in MoSe2 monolayers
• Magnetoelectric effects and valley controlled spin quantum gates in transition metal dichalcogenide bilayers
• Anomalous Interlayer Exciton Diffusion in Twist-Angle-Dependent Moiré Potentials of WS${}_2$-WSe${}_2$ Heterobilayers
• Nonlinear Photoluminescence in Atomically Thin Layered WSe2 Arising from Diffusion-Assisted Exciton-Exciton Annihilation
• Ultrafast transition between exciton phases in van der Waals heterostructures
• Excitons versus electron-hole plasma in monolayer transition metal dichalcogenide semiconductors
• Dipolar interactions between field-tuneable, localized emitters in van der Waals heterostructures
• Analysis of the exciton-exciton interaction in semiconductor quantum wells
• Interlayer exciton dynamics in a dichalcogenide monolayer heterostructure
• The dielectric impact of layer distances on exciton and trion binding energies in van der Waals heterostructures
• Exciton correlations in coupled quantum wells and their luminescence blue shift
• Excitonic transport driven by repulsive dipolar interaction in a van der Waals heterostructure
• Ultrafast Band Structure Control of a Two-Dimensional Heterostructure
• RESPACK: An ab initio tool for derivation of effective low-energy model of material
• Interlayer excitons in MoSe${}_2$/WSe${}_2$ heterostructures from first-principles
• Quantum diffusion of dipole-oriented indirect excitons in coupled quantum wells
• Excitons in mesoscopically reconstructed moiré heterostructures
• Diffusivity Reveals Three Distinct Phases of Interlayer Excitons in MoSe2/WSe2 Heterobilayers
• Wannier Function Approach to Realistic Coulomb Interactions in Layered Materials and Heterostructures
• Condensation signatures of photogenerated interlayer excitons in a van der Waals heterostack
• Nonclassical Exciton Diffusion in Monolayer WSe2
• The Effective Bosonic Hamiltonian for Excitons Reconsidered
• Moiré-Bose-Hubbard model for interlayer excitons in twisted transition metal dichalcogenide heterostructures
• Exciton lifetime and optical linewidth profile via exciton-phonon interactions: Theory and first-principles calculations for monolayer MoS${}_2$
• Excitation-induced transition to indirect band gaps in atomically thin transition metal dichalcogenide semiconductors
• Optical control of valley Zeeman effect through many-exciton interactions
• Microscopic origin of anomalous interlayer exciton transport in van der Waals heterostructures
• Fundamental exciton linewidth broadening in monolayer transition metal dichalcogenides
• Coulomb-Engineered Heterojunctions and Dynamical Screening in Transition Metal Dichalcogenide Monolayers
• Interplay of screening and superconductivity in low-dimensional materials
• Exciton-phonon-scattering: A competition between bosonic and fermionic nature of bound electron-hole pairs
• Theory of condensation of indirect excitons in a trap
• Confined-state physics and signs of fermionization of moiré excitons in WSe${}_2$/MoSe${}_2$ heterobilayers
• Ab initio electron-lattice downfolding: potential energy landscapes, anharmonicity, and molecular dynamics in charge density wave materials

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• Exciton fractional Chern insulators in moiré heterostructures
• Striped excitonic (super)solid in anisotropic semiconductors with screened exciton interactions
• Electrically tunable MoSe${}_2$/WSe${}_2$ heterostructure-based quantum dot
• Intersubband electric dipole spin resonance in transition metal dichalcogenide heterobilayers
• Variational and field-theoretical approach to exciton-exciton interactions and biexcitons in semiconductors
• Ferroelectric Control of Interlayer Excitons in 3R-MoS${}_2$ / MoSe${}_2$ Heterostructures
• Tracking the photoinduced dynamics of a dark excitonic state in single-layer WS${}_2$ via resonant Autler-Townes splitting
• Effective long-range attraction of moiré excitons under the influence of atomic reconstructions and anisotropic screening
• Quantum siphoning of finely spaced interlayer excitons in reconstructed MoSe2/WSe2 heterostructures