Magnetically brightened dark electron-phonon bound states in a van der Waals antiferromagnet

Abstract

In van der Waals (vdW) materials, strong coupling between different degrees of freedom can hybridize elementary excitations into bound states with mixed character. Correctly identifying the nature and composition of these bound states is key to understanding their ground state properties and excitation spectra. Here, we use ultrafast spectroscopy to reveal bound states of d-orbitals and phonons in 2D vdW antiferromagnet NiPS3. These bound states manifest themselves through equally spaced phonon replicas in frequency domain. These states are optically dark above the Néel temperature and become accessible with magnetic order. By launching this phonon and spectrally tracking its amplitude, we establish the electronic origin of bound states as localized d-d excitations. Our data directly yield electron-phonon coupling strength which exceeds the highest known value in 2D systems. These results demonstrate NiPS3 as a platform to study strong interactions between spins, orbitals and lattice, and open pathways to coherent control of 2D magnets.

References in corpus (7)

• Magnetic 2D materials and heterostructures
• Superconductivity in single-layer films of FeSe with a transition temperature above 100 K
• Resolving photon number states in a superconducting circuit
• Suppression of magnetic ordering in XXZ-type antiferromagnetic monolayer NiPS3
• Linear magneto-electric phase in ultrathin MnPS${}_3$ probed by optical second harmonic generation
• Universal Substrate Effect on the Superconductivity of FeSe Monolayer Films
• Phonon driven Floquet matter

Cited by in corpus (19)

• The bulk van der Waals layered magnet CrSBr is a quasi-1D material
• Terahertz field-induced metastable magnetization near criticality in FePS3
• Progress and Prospects in Two-Dimensional Magnetism of van der Waals Materials
• 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 demagnetization in ferromagnetic materials: Origins and progress
• Coherent detection of hidden spin-lattice coupling in a van der Waals antiferromagnet
• Observation of three-state nematicity and domain evolution in atomically-thin antiferromagnetic NiPS3
• Magnetoelectric effect in van der Waals magnets
• Exciton-magnon splitting in van der Waals antiferromagnet MnPS${}_3$ unveiled by second-harmonic generation
• Spin model for the Honeycomb $\mathrm{NiP}{\mathrm{S}}_3$
• Brightened Optical Transition as Indicator of Multiferroicity in a Layered Antiferromagnet
• Long-lived population inversion in resonantly driven excitonic antiferromagnet
• Electronic structure of the frustrated diamond lattice magnet NiRh${}_2$O${}_4$
• Terahertz Control of Linear and Nonlinear Magno-Phononics
• Quantum Fluctuations in the van der Walls material $\mathrm{NiP}{\mathrm{S}}_3$
• Tunable phononic coupling in excitonic quantum emitters
• Crystal field tuned spin-flip luminescence in NiPS3
• Ultrafast Dynamics of Spin-Orbit Entangled Excitons Coupled to Magnetic Ordering in van der Waals Antiferromagnet NiPS3