Lattice dynamics and structural transition of the hyperhoneycomb iridate $\beta$-Li${}_2$IrO${}_3$ investigated by high-pressure Raman scattering

Abstract

We report a polarized Raman scattering study of the lattice dynamics of $\beta$-Li${}_2$IrO${}_3$ under hydrostatic pressures up to 7.62 GPa. At ambient pressure, $\beta$-Li${}_2$IrO${}_3$ exhibits the hyperhoneycomb crystal structure and a magnetically ordered state of spin-orbit entangled Jeff = 1/2 moments that is strongly influenced by bond-directional (Kitaev) exchange interactions. At a critical pressure of ~ 4.1 GPa, the phonon spectrum changes abruptly consistent with the reported structural transition into a monoclinic, dimerized phase. A comparison to the phonon spectra obtained from density functional calculations shows reasonable overall agreement. The calculations also indicate that the high-pressure phase is a nonmagnetic insulator driven by the formation of Ir-Ir dimer bonds. Our results thus indicate a strong sensitivity of the electronic properties of $\beta$-Li${}_2$IrO${}_3$ to the pressure-induced structural transition.

arXiv comment16 pages, 7 figures, 5 tables, Supplemental Material included

References in corpus (57)

• Anyons in an exactly solved model and beyond
• Mott Insulators in the Strong Spin-Orbit Coupling Limit: From Heisenberg to a Quantum Compass and Kitaev Models
• Correlated quantum phenomena in the strong spin-orbit regime
• Kitaev-Heisenberg Model on Honeycomb Lattice: Possible Exotic Phases in Iridium Oxides $A_2$IrO${}_3$
• Proximate Kitaev Quantum Spin Liquid Behaviour in α-RuCl${}_3$
• $\alpha$-RuCl3: a Spin-Orbit Assisted Mott Insulator on a Honeycomb Lattice
• Relevance of the Heisenberg-Kitaev model for the honeycomb lattice iridates A_2IrO_3
• Quantum Monte Carlo Impurity Solver for Cluster DMFT and Electronic Structure Calculations in Adjustable Base
• Models and Materials for Generalized Kitaev Magnetism
• Dynamical Mean-Field Theory within the Full-Potential Methods: Electronic structure of Ce-115 materials
• Spin waves and revised crystal structure of honeycomb iridate Na2IrO3
• On the Origin of Zigzag Magnetic Order in Iridium Oxide Na2IrO3
• Challenges in Design of Kitaev Materials: Magnetic Interactions from Competing Energy Scales
• The monoclinic crystal structure of $\alpha$-RuCl${}_3$ and the zigzag antiferromagnetic ground state
• Direct evidence of a zigzag spin chain structure in the honeycomb lattice: A neutron and x-ray diffraction investigation on single crystal $\mathrm{N}{\mathrm{a}}_2\mathrm{Ir}{\mathrm{O}}_3$
• Hyper-honeycomb iridate $\beta$-Li2IrO3 as a platform for Kitaev magnetism
• Long range magnetic ordering in Na${}_2$IrO${}_3$
• A new spin-anisotropic harmonic honeycomb iridate
• Kitaev interactions between j=1/2 moments in honeycomb Na2IrO3 are large and ferromagnetic: insights from ab initio quantum chemistry calculations
• Exactly solvable Kitaev model in three dimensions
• Incommensurate Counterrotating Magnetic Order Stabilized by Kitaev Interactions in the Layered Honeycomb $\alpha$-Li${}_2$IrO${}_3$
• Non-coplanar and counter-rotating incommensurate magnetic order stabilized by Kitaev interactions in $\gamma$-Li2IrO3
• Unconventional magnetic order on the hyperhoneycomb Kitaev lattice in $\beta$-Li2IrO3: full solution via magnetic resonant x-ray diffraction
• Effective J=1/2 insulating state in Ruddlesden-Popper iridates: An LDA+DMFT study
• Covalent bonds against magnetism in transition metal compounds
• Raman spectroscopic signature of fractionalized excitations in the harmonic-honeycomb iridates $\beta$- and $\gamma$-Li${}_2$IrO${}_3$
• Pressure-induced dimerization and valence bond crystal formation in the Kitaev-Heisenberg magnet alpha-RuCl3
• Metal-insulator transition and topological properties of pyrochlore iridates
• Heisenberg-Kitaev model on hyperhoneycomb lattice
• Forces for Structural Optimizations in Correlated Materials within DFT+Embedded DMFT Functional Approach
• Competition between spin-orbit coupling, magnetism, and dimerization in the honeycomb iridates: $\alpha$-Li${}_2$IrO${}_3$ under pressure
• Raman scattering from Higgs mode oscillations in the two-dimensional antiferromagnet Ca${}_2$RuO${}_4$
• Unified theory of spiral magnetism in the harmonic-honeycomb iridates α, β, γ Li2IrO3
• Two-magnon Raman scattering and pseudospin-lattice interactions in Sr2IrO4 and Sr3Ir2O7
• Single crystal growth from separated educts and its application to lithium transition-metal oxides
• Breakdown of magnetic order in the pressurized Kitaev iridate $\beta$-Li${}_2$IrO${}_3$
• Pressure-tuned magnetic interactions in honeycomb Kitaev materials
• Pressure-tuning of bond-directional exchange interactions and magnetic frustration in hyperhoneycomb iridate $\beta$-$\mathrm{L}{\mathrm{i}}_2\mathrm{Ir}{\mathrm{O}}_3$
• Detuning the Honeycomb of $\alpha$-RuCl${}_3$: Pressure-Dependent Optical Studies Reveal Broken Symmetry
• Raman evidence for dimerization and Mott collapse in $\alpha$-RuCl${}_3$ under pressures
• Magnetic structure and excitation spectrum of the hyperhoneycomb Kitaev magnet $\beta$-Li${}_2$IrO${}_3$
• Magnetic structure, magnetoelastic coupling, and thermal properties of EuCrO${}_3$ nano-powders
• Two iridates, two models, two approaches: a comparative study on magnetism in 3D honeycomb materials
• Pressure-driven collapse of the relativistic electronic ground state in a honeycomb iridate
• Pressure-induced collapse of spin-orbital Mott state in the hyperhoneycomb iridate $\beta$-Li${}_2$IrO${}_3$
• Predominance of the Kitaev interaction in a three-dimensional honeycomb iridate: from ab-initio to spin model
• Resonant x-ray scattering reveals possible disappearance of magnetic order under hydrostatic pressure in the Kitaev candidate $\gamma$-Li${}_2$IrO${}_3$
• Revealing frustrated local moment model for pressurized hyperhoneycomb iridate: paving a way toward quantum spin liquid
• Spin dynamics and field-induced magnetic phase transition in the honeycomb Kitaev magnet $\alpha$-Li${}_2$IrO${}_3$
• High-pressure versus isoelectronic doping effect on the honeycomb iridate Na${}_2$IrO${}_3$
• Chemical- and hydrostatic-pressure effects on the Kitaev honeycomb material Na${}_2$IrO${}_3$
• Bond ordering and phase transitions in Na${}_2$IrO${}_3$ under high pressure
• Pressure-induced structural dimerization in the hyperhoneycomb iridate $\beta$-Li${}_2$IrO${}_3$ at low temperatures
• Pressure-induced Phonon Softenings and the Structural and Magnetic Transitions in CrO${}_2$
• Topological and magnetic phases with strong spin-orbit coupling on the hyperhoneycomb lattice
• Optical signature of the pressure-induced dimerization in the honeycomb iridate $\alpha$-Li${}_2$IrO${}_3$
• Structural investigation of the insulator-metal transition in NiS${}_{2-x}$Se${}_x$ compounds

Cited by in corpus (4)

• Kitaev magnetism through the prism of lithium iridate
• Resonant inelastic x-ray scattering spectra in the hyperhoneycomb iridate $\beta$-Li${}_2$IrO${}_3$: First principles calculations
• Interplay of magnetism and dimerization in pressurized Kitaev material $\beta$-Li${}_2$IrO${}_3$
• Evolution of electronic and magnetic properties of Sr${}_2$IrO${}_4$ under strain