Physical origin of giant excitonic and magneto-optical responses in two-dimensional ferromagnetic insulators

Abstract

The recent discovery of magnetism in atomically thin layers of van der Waals crystals has created great opportunities for exploring light-matter interactions and magneto-optical phenomena in the two-dimensional limit. Optical and magneto-optical experiments have provided insights into these topics, revealing strong magnetic circular dichroism and giant Kerr signals in atomically thin ferromagnetic insulators. However, the nature of the giant magneto-optical responses and their microscopic mechanism remain unclear. Here, by performing first-principles GW and Bethe-Salpeter equation calculations, we show that excitonic effects dominate the optical and magneto-optical responses in the prototypical two-dimensional ferromagnetic insulator, CrI${}_3$. We simulate the Kerr and Faraday effects in realistic experimental setups, and based on which we predict the sensitive frequency- and substrate-dependence of magneto-optical responses. These findings provide physical understanding of the phenomena as well as potential design principles for engineering magneto-optical and optoelectronic devices using two-dimensional magnets.

To appear in Nature Communications

References in corpus (6)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Probing Excitonic Dark States in Single-layer Tungsten Disulfide
• Exciton band structure of monolayer MoS2
• The f-electron challenge: localized and itinerant states in lanthanide oxides united by GW@LDA+U
• Non-uniform sampling schemes of the Brillouin zone for many-electron perturbation-theory calculations in reduced dimensionality
• Magnetism and Magneto-optical Effects in Bulk and Few-layer CrI${}_3$: A Theoretical GGA + U Study

Cited by in corpus (49)

• Interlayer Electronic Coupling on Demand in a 2D Magnetic Semiconductor
• Magneto-optics in a van der Waals magnet tuned by self-hybridized polaritons
• Highly Anisotropic Excitons and Multiple Phonon Bound States in a Van der Waals Antiferromagnetic Insulator
• Magnetic Two-Dimensional Chromium Trihalides: A Theoretical Perspective
• Tuning Inelastic Light Scattering via Symmetry Control in 2D Magnet CrI${}_3$
• Artificial Multiferroics and Enhanced Magnetoelectric Effect in van der Waals Heterostructures
• Electrically tunable moiré magnetism in twisted double bilayers of chromium triiodide
• Spin Dynamics in van der Waals Magnetic Systems
• Spin Photovoltaic Effect in Magnetic van der Waals Heterostructures
• Spin dynamics slowdown near the antiferromagnetic critical point in atomically thin FePS3
• Progress and Prospects in Two-Dimensional Magnetism of van der Waals Materials
• Spinorial formulation of the GW-BSE equations and spin properties of excitons in 2D Transition Metal Dichalcogenides
• Magneto-optical Kerr effect in ferroelectric antiferromagnetic two-dimensional heterostructures
• Electronic Structure of Chromium Trihalides beyond Density Functional Theory
• Optical and magneto-optical properties of ferromagnetic monolayer CrBr${}_3$: A first-principles $GW$ and $GW$ plus Bethe-Salpeter equation study
• Unified Treatment of Magnons and Excitons in Monolayer CrI${}_3$ from Many-Body Perturbation Theory
• Giant proximity exchange and flat Chern band in 2D magnet-semiconductor heterostructures
• Emergence of electric-field-tunable interfacial ferromagnetism in 2D antiferromagnet heterostructures
• Large-gap insulating dimer ground state in monolayer IrTe2
• Magneto-optical Kerr effect and magnetoelasticity in weak ferromagnetic RuF${}_4$ monolayer
• AC susceptometry of 2D van der Waals magnets enabled by the coherent control of quantum sensors
• Chirality of Valley Excitons in Monolayer Transition-Metal Dichalcogenides
• Anisotropic Electron-Hole Excitation and Large Linear Dichroism in Two-Dimensional Ferromagnet CrSBr with In-Plane Magnetization
• The first- and second-order magneto-optical effects and intrinsically anomalous transport in 2D van der Waals layered magnets CrXY (X = S, Se, Te; Y = Cl, Br, I)
• Delocalization of dark and bright excitons in flat-band materials and the optical properties of V${}_2$O${}_5$
• Tunneling current-controlled spin states in few-layer van der Waals magnets
• Exchange splitting and exchange-induced non-reciprocal photonic behavior of graphene in CrI3-graphene vdW heterostructures
• On-site and inter-site Hubbard corrections in magnetic monolayers: The case of FePS${}_3$ and CrI${}_3$
• All optical resonant magnetization switching in ${\text{CrI}}_3$ monolayers
• Mechanism of carrier doping induced magnetic phase transitions in two-dimensional materials
• Electronic structure of van der Waals ferromagnet CrI${}_3$ from self consistent vertex corrected GW approaches
• Activating magnetoelectric optical properties by twisting antiferromagnetic bilayers
• Superexchange and spin-orbit coupling in monolayer and bilayer chromium trihalides
• Enhancing magneto-optic effects in two-dimensional magnets by thin-film interference
• Engineering of a Layered Ferromagnet via Graphitization: An Overlooked Polymorph of GdAlSi
• Electrical tuning of the magnetic properties of 2D magnets: the case of ${\mathrm{Cr}}_2{\mathrm{Ge}}_2{\mathrm{Te}}_6$
• Dispersive dark excitons in van der Waals ferromagnet CrI3
• Robust polaritons in magnetic monolayers of CrI3
• Distinguishing Surface and Bulk Electromagnetism via Their Dynamics in an Intrinsic Magnetic Topological Insulator
• Enhanced Magnetization by Defect-Assisted Exciton Recombination in Atomically Thin CrCl${}_3$
• Band-spin-valley coupled exciton physics in antiferromagnetic MnPS${}_3$
• Optical properties of monolayer, multilayer, and bulk BiI${}_3$ studied using time-dependent density functional theory
• Interlayer superexchange in bilayer chromium trihalides
• Light-induced ultrafast magnetization dynamics in van der Waals antiferromagnetic CrSBr
• Environmental Screening and Ligand-Field Effects to Magnetism in CrI${}_3$ Monolayer
• Excitonic optical absorption in strained monolayer CrSBr
• Flipping of electronic spins in BiFeO${}_3$ via chiral $d-d$ excitations
• Electrostatic Control of Magneto-Optic Excitonic Resonances in the van der Waals Ferromagnetic Semiconductor Cr${}_2$Ge${}_2$Te${}_6$
• Solvers for the Hermitian and the pseudo-Hermitian Bethe-Salpeter equation in the Yambo code: Implementation and Performance