Exciton-driven antiferromagnetic metal in a correlated van der Waals insulator

Abstract

Collective excitations of bound electron-hole pairs -- known as excitons -- are ubiquitous in condensed matter, emerging in systems as diverse as band semiconductors, molecular crystals, and proteins. Recently, their existence in strongly correlated electron materials has attracted increasing interest due to the excitons' unique coupling to spin and orbital degrees of freedom. The non-equilibrium driving of such dressed quasiparticles offers a promising platform for realizing unconventional many-body phenomena and phases beyond thermodynamic equilibrium. Here, we achieve this in the van der Waals correlated insulator NiPS${}_3$ by photoexciting its newly discovered spin-orbit-entangled excitons that arise from Zhang-Rice states. By monitoring the time evolution of the terahertz conductivity, we observe the coexistence of itinerant carriers produced by exciton dissociation and the long-wavelength antiferromagnetic magnon that coherently precesses in time. These results demonstrate the emergence of a transient metallic state that preserves long-range antiferromagnetism, a phase that cannot be reached by simply tuning the temperature. More broadly, our findings open an avenue toward the exciton-mediated optical manipulation of magnetism.

24 pages, 23 figures

References in corpus (4)

• Suppression of magnetic ordering in XXZ-type antiferromagnetic monolayer NiPS3
• Excitonic quasiparticles in a spin-orbit Mott insulator
• Hubbard exciton revealed by time-domain optical spectroscopy
• Raman scattering study of vibrational and magnetic excitations in Sr${}_{2-x}$La${}_x$IrO${}_4$

Cited by in corpus (32)

• Tunable Exciton-Hybridized Magnon Interactions in a Layered Semiconductor
• Spin-correlated exciton-polaritons in a van der Waals magnet
• Limited ferromagnetic interactions in monolayers of MPS${}_3$ (M=Mn, Ni)
• The magnetic dynamics of NiPS${}_3$
• Terahertz field-induced metastable magnetization near criticality in FePS3
• Spin Dynamics in van der Waals Magnetic Systems
• Magnetically propagating Hund's exciton in van der Waals antiferromagnet NiPS3
• Progress and Prospects in Two-Dimensional Magnetism of van der Waals Materials
• Spin wave Hamiltonian and anomalous scattering in NiPS${}_3$
• Electronic band structure changes across the antiferromagnetic phase transition of exfoliated MnPS${}_3$ probed by $\mu$-ARPES
• Ultrafast laser-induced spin-lattice dynamics in the van der Waals antiferromagnet CoPS3
• Ultrafast optical excitation of magnetic dynamics in van der Waals magnets: Coherent magnons and BKT dynamics in NiPS${}_3$
• Observation of three-state nematicity and domain evolution in atomically-thin antiferromagnetic NiPS3
• Giant spin Nernst effect in a two-dimensional antiferromagnet due to magnetoelastic coupling-induced gaps and interband transitions between magnon-like bands
• Magnetoelectric effect in van der Waals magnets
• Direct Observation and Analysis of Low-Energy Magnons with Raman Spectroscopy in Atomically Thin NiPS3
• Exciton-magnon splitting in van der Waals antiferromagnet MnPS${}_3$ unveiled by second-harmonic generation
• Laser-induced Demagnetization in van der Waals $XY$- and Ising-like Antiferromagnets NiPS${}_3$ and FePS${}_3$
• Distinct Optical Excitation Mechanisms of a Coherent Magnon in a van der Waals Antiferromagnet
• Spin model for the Honeycomb $\mathrm{NiP}{\mathrm{S}}_3$
• Optical-pump terahertz-probe spectroscopy in high magnetic fields with kHz single-shot detection
• Phonon-mediated strong coupling between a three-dimensional topological insulator and a two-dimensional antiferromagnetic material
• Brightened Optical Transition as Indicator of Multiferroicity in a Layered Antiferromagnet
• Long-lived population inversion in resonantly driven excitonic antiferromagnet
• Characteristic exciton energy scales in antiferromagnetic NiPS${}_3$
• Enhanced Magnetization by Defect-Assisted Exciton Recombination in Atomically Thin CrCl${}_3$
• Quantum Fluctuations in the van der Walls material $\mathrm{NiP}{\mathrm{S}}_3$
• Change in Magnetic Order in NiPS3 Single Crystals Induced by a Molecular Intercalation
• Exciton-spin interactions in antiferromagnetic charge-transfer insulators
• Excitonic optical absorption in strained monolayer CrSBr
• Ultrafast Dynamics of Spin-Orbit Entangled Excitons Coupled to Magnetic Ordering in van der Waals Antiferromagnet NiPS3
• Coherent Spin-Phonon Coupling in the Layered Ferrimagnet Mn3Si2Te6