Ultrafast Electronic Band Gap Control in an Excitonic Insulator

Abstract

We report on the nonequilibrium dynamics of the electronic structure of the layered semiconductor Ta${}_2$NiSe${}_5$ investigated by time- and angle-resolved photoelectron spectroscopy. We show that below the critical excitation density of $F_C=0.2$ mJ cm${}^{-2}$, the band gap $narrows$ transiently, while it is $enhanced$ above $F_C$. Hartree-Fock calculations reveal that this effect can be explained by the presence of the low-temperature excitonic insulator phase of Ta${}_2$NiSe${}_5$, whose order parameter is connected to the gap size. This work demonstrates the ability to manipulate the band gap of Ta${}_2$NiSe${}_5$ with light on the femtosecond time scale.

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Cited by in corpus (116)

• Coherent Order Parameter Oscillations in the Ground State of the Excitonic Insulator Ta2NiSe5
• Superradiant Quantum Materials
• Time- and Angle-Resolved Photoemission Studies of Quantum Materials
• Nature of symmetry breaking at the excitonic insulator transition: Ta${}_2$NiSe${}_5$
• Photo-induced semimetallic states realised in electron-hole coupled insulators
• Strong Coupling Nature of the Excitonic Insulator State in Ta${}_2$NiSe${}_5$
• Direct observation of excitonic instability in Ta2NiSe5
• Photo-induced enhancement of excitonic order
• Electron-Phonon Coupling Mode in Excitonic Insulator
• Band hybridisation at the semimetal-semiconductor transition of Ta${}_2$NiSe${}_5$ enabled by mirror-symmetry breaking
• Fast Green's function method for ultrafast electron-boson dynamics
• $\eta$--paired superconducting hidden phase in photodoped Mott insulators
• Non-Coulomb strong electron-hole binding in $T{a}_{2}NiS{e}_5$ revealed by time- and angle-resolved photoemission spectroscopy
• Imaging the coherent propagation of collective modes in the excitonic insulator candidate Ta${}_2$NiSe${}_5$ at room temperature
• Inhibition of the photoinduced structural phase transition in the excitonic insulator Ta${}_2$NiSe${}_5$
• Collective Modes in Excitonic Insulators: Effects of Electron-Phonon Coupling and Signatures in Optical Response
• Photoinduced multistage phase transitions in Ta2NiSe5
• Exciton-phonon cooperative mechanism of the triple-$q$ charge-density-wave and antiferroelectric electron polarization in TiSe${}_2$
• Detecting electron-phonon couplings during photo-induced phase transition
• Theoretical Understanding of Photon Spectroscopies in Correlated Materials In and Out of Equilibrium
• Resonant thermalization of periodically driven strongly correlated electrons
• Realizing intrinsic excitonic insulator by decoupling exciton binding energy from the minimum band gap
• Orthorhombic-to-monoclinic transition in Ta${}_2$NiSe${}_5$ due to a zone-center optical phonon instability
• Ultrafast melting and recovery of collective order in the excitonic insulator Ta${}_2$NiSe${}_5$
• Comparing the generalized Kadanoff-Baym ansatz with the full Kadanoff-Baym equations for an excitonic insulator out of equilibrium
• Entropy-cooled nonequilibrium states of the Hubbard model
• Pump driven normal-to-excitonic insulator transition: Josephson oscillations and signatures of BEC-BCS crossover in time-resolved ARPES
• Tuning time and energy resolution in time-resolved photoemission spectroscopy with nonlinear crystals
• Ultrafast dynamics of hot charge carriers in an oxide semiconductor probed by femtosecond spectroscopic ellipsometry
• Phononic soft mode and strong electronic background behavior across the structural phase transition in the excitonic insulator Ta${}_2$NiSe${}_5$ (with Erratum)
• Truncating the memory time in nonequilibrium DMFT calculations
• Ultrafast nonequilibrium evolution of excitonic modes in semiconductors
• Photo-induced phase transition and associated time scales in the excitonic insulator Ta${}_2$NiSe${}_5$
• Dynamics of photo-doped charge transfer insulators
• Quantum Boltzmann equation for strongly correlated systems: comparison to dynamical mean field theory
• Lattice dynamics of the excitonic insulator Ta${}_2$Ni(Se${}_{1-x}$S${}_x$)${}_5$
• Transient Floquet engineering of superconductivity
• Enhanced pairing susceptibility in a photo-doped two-orbital Hubbard model
• Role of electron-phonon coupling in excitonic insulator candidate Ta2NiSe5
• Exciton-Driven Renormalization of Quasiparticle Band Structure in Monolayer MoS2
• Nonequilibrium steady-state theory of photodoped Mott insulators
• Photoinduced $\eta$-pairing at finite temperatures
• Photoinduced enhancement of excitonic order in the two-orbital Hubbard model
• Hybridization-gap Formation and Superconductivity in the Pressure-induced Semimetallic Phase of the Excitonic Insulator Ta${}_2$NiSe${}_5$
• Effect of Cu intercalation and pressure on excitonic interaction in 1T-TiSe2
• Nonlinear spectroscopy of collective modes in excitonic insulator
• A New Era of Excitonic Insulators
• Photo-induced nonequilibrium states in Mott insulators
• Photo-excited Dynamics in the Excitonic Insulator Ta2NiSe5
• Nonequilibrium dynamics in the pump-probe spectroscopy of excitonic insulators
• A quantum Boltzmann equation for strongly correlated electrons
• Unveiling the underlying interactions in Ta2NiSe5 from photo-induced lifetime change
• Signatures of ultrafast reversal of excitonic order in Ta${}_2$NiSe${}_5$
• Disentangling lattice and electronic instabilities in the excitonic insulator candidate Ta${}_2$NiSe${}_5$ by nonequilibrium spectroscopy
• Photoinduced coherent modulation of an excitonic resonance via coupling with coherent optical phonons
• Nonequilibrium dynamics in pumped Mott insulators
• Advancing time- and angle-resolved photoemission spectroscopy: The role of ultrafast laser development
• Ultrafast Switching from the Charge Density Wave Phase to a Metastable Metallic State in 1T-TiSe${}_2$
• Adiabatic Preparation of a Correlated Symmetry-Broken Initial State with the Generalized Kadanoff--Baym Ansatz
• Phonon-assisted electronic states modulation of few-layer PdSe2 at terahertz frequencies
• Collective excitations of the U(1)-symmetric exciton insulator in a cavity
• Electronic and fluctuation dynamics following a quench to the superconducting phase
• Noise Correlations in time- and angular-resolved photoemission spectroscopy
• Photoinduced renormalization of Dirac states in BaNiS${}_2$
• Photoinduced electron-electron pairing in the extended Falicov-Kimball model
• Ultrafast creation of a light induced semimetallic state in strongly excited 1T-TiSe${}_2$
• Tunneling-tip-induced collapse of the charge gap in the excitonic insulator Ta${}_2$NiSe${}_5$
• Ultrafast charge carrier and exciton dynamics in an excitonic insulator probed by time-resolved photoemission spectroscopy
• Transient Hot Electron Dynamics in Single-Layer TaS${}_2$
• Tightly bound excitons in two-dimensional semiconductors with a flat valence band
• Role of matrix elements in the time-resolved photoemission signal
• Evolution of the electronic structure in Ta${}_2$NiSe${}_5$ across the structural transition revealed by resonant inelastic x-ray scattering
• Accelerated gap collapse in a Slater antiferromagnet
• Nonthermal excitonic condensation near a spin-state transition
• Effects of Disorder on the Transport of Collective Modes in an Excitonic Condensate
• Non-thermal superconductivity in photo-doped multi-orbital Hubbard systems
• Thermal transport signatures of the excitonic transition and associated phonon softening in the layered chalcogenide Ta${}_2$NiSe${}_5$
• Photoinduced metallization of excitonic insulators
• Nonthermal switching of charge order: dynamical slowing down and optimal control
• Finite-temperature photoemission in the extended Falicov-Kimball model: a case study for Ta${}_2$NiSe${}_5$
• Pressure suppression of the excitonic insulator state in Ta2NiSe5 observed by optical conductivity
• Photoinduced Enhancement of Anisotropic Charge Correlations on Triangular Lattices with Trimers
• Third-harmonic generation in excitonic insulators
• Theory of time-crystalline behaviour mediated by phonon squeezing in Ta2NiSe5
• Momentum-Resolved Signatures of Carrier Screening Effects on Electron-Phonon Coupling in MoS${}_2$
• Effect of photoinduced screening on the spectroscopic signature of exciton-phonon coupling
• Steady off-diagonal long-range order state in a half-filled dimerized Hubbard chain induced by a resonant pulsed field
• Photo-induced Dirac cone flattening in BaNiS${}_2$
• Excitonic Order and Superconductivity in the Two-Orbital Hubbard Model: Variational Cluster Approach
• Direct observation of multiple conduction-band minima in high-performance thermoelectric SnSe
• Laser-induced ultrafast insulator-metal transition in ${\text{BaBiO}}_3$
• Collective modes and Raman response in Ta${}_2$NiSe${}_5$
• Charge Oscillations Emerging after Application of an Intense Light Field to Superconductors on a Dimer Lattice
• Interlayer excitonic insulator in two-dimensional double-layer semiconductor junctions: An explicitly solvable model
• Light-induced switching of magnetic order in the anisotropic triangular-lattice Hubbard model
• Optical Response in Excitonic Insulating State: Variational Cluster Approach
• Photoinduced High-Frequency Charge Oscillations in Dimerized Systems
• Orbitally Selective Resonant Photodoping to Enhance Superconductivity
• Superconducting optical response of photodoped Mott insulators
• Ultrafast dynamics in (TaSe${}_4$)${}_2$I triggered by valence and core-level excitation
• Quantum Transport Properties of an Exciton Insulator/Superconductor Hybrid Junction
• Electronic band structure in pristine and Sulfur-doped Ta${}_2$NiSe${}_5$
• Interacting electrons in a flat-band system within the Generalized Kadanoff-Baym Ansatz
• Photo-induced Dynamics of Quasicrystalline Excitonic Insulator
• Photoinduced dynamics of excitonic order and Rabi oscillation in the two-orbital Hubbard model
• Anomalous phonon Grüneisen parameters in semiconductor Ta${}_2$NiS${}_5$
• Gate tuning of coupled electronic and structural phase transition in atomically thin Ta${}_2$NiSe${}_5$
• High-resolution MHz time- and angle-resolved photoemission spectroscopy based on a tunable vacuum ultraviolet source
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• Prolonged photo-carriers generated in a massive-and-anisotropic Dirac material
• Time-Resolved Photoemission Spectroscopy of Quantum Materials Using High Harmonic Generation: Probing Electron-Phonon Interactions and Non-Equilibrium Dynamics
• Mechanism for Synchronization of Charge Oscillations in Dimer Lattices
• Long-lived relaxation channel and exciton-phonon coupling in Ta2NiSe5 via non-degenerate pump-probe spectroscopy
• Nonequilibrium Dynamics in a Quantum Spin Chain with Pump-Probe Resonant Inelastic X-ray Scattering
• Photoinduced excitonic magnetism in a multiorbital Hubbard system
• Probing the collective excitations of excitonic insulators in an optical cavity