Lattice frustration in spin-orbit Mott insulator Sr3Ir2O7 at high pressure

Abstract

The intertwined charge, spin, orbital, and lattice degrees of freedom could endow 5d compounds with exotic properties. Current interest is focused on electromagnetic interactions in these materials, whereas the important role of lattice geometry remains to be fully recognized. For this sake, we investigate pressure-induced phase transitions in the spin-orbit Mott insulator Sr3Ir2O7 with Raman, electrical resistance, and x-ray diffraction measurements. We reveal an interesting magnetic transition coinciding with a structural transition at 14.4 GPa, but without a concurrent insulator-metal transition. The conventional correlation between magnetic and Mott insulating states is thereby absent. The observed softening of the one-magnon mode can be explained by a reduced tetragonal distortion, while the actual magnetic transition is associated with tilting of the IrO6 octahedra. This work highlights the critical role of lattice frustration in determining the high-pressure phases of Sr3Ir2O7. The ability to control electromagnetic properties via manipulating the crystal structure with pressure promises a new way to explore new quantum states in spin-orbit Mott insulators.

6 pages, 5 figures

References in corpus (31)

• Electronic Structure of Pyrochlore Iridates: From Topological Dirac Metal to Mott Insulator
• 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
• On the Origin of Zigzag Magnetic Order in Iridium Oxide Na2IrO3
• Twisted Hubbard Model for Sr2IrO4: Magnetism and Possible High Temperature Superconductivity
• Monte Carlo study of an unconventional superconducting phase in Ir-oxide J_{eff}=1/2 Mott insulators induced by carrier doping
• Lattice-Driven Magnetoresistivity and Metal-Insulator Transition in Single-Layered Iridates
• The Challenge of Spin-Orbit-Tuned Ground States in Iridates
• Giant Magnon Gap in Bilayer Iridate Sr3Ir2O7: Enhanced Pseudo-dipolar Interactions Near the Mott Transition
• Dimensionality Driven Spin-Flop Transition in Layered Iridates
• Tetrahedral Magnetic Order and the Metal-Insulator Transition in the Pyrochlore Lattice of Cd2Os2O7
• Critical properties of the Kitaev-Heisenberg model
• Spin-orbit tuned metal-insulator transitions in single-crystal Sr2Ir1-xRhxO4 (0\leqx\leq1)
• Pseudo Jahn-Teller Effect and Magnetoelastic Coupling in Spin-Orbit Mott Insulators
• Two-magnon Raman scattering and pseudospin-lattice interactions in Sr2IrO4 and Sr3Ir2O7
• Noncollinear magnetism and spin-orbit coupling in 5d pyrochlore oxide Cd2Os2O7
• Magnetic state of pyrochlore Cd2Os2O7 emerging from strong competition of ligand distortions and longer-range crystalline anisotropy
• A Novel High-Pressure Monoclinic Metallic Phase of V2O3
• Tuning Jeff = 1/2 Insulating State via Electron Doping and Pressure in Double-Layered Iridate Sr3Ir2O7
• A charge density wave-like instability in a doped spin-orbit-assisted weak Mott insulator
• Evidence of quantum dimer excitations in Sr${}_3$Ir${}_2$O${}_7$
• Crossover from coherent to incoherent scattering in spin-orbit dominated Sr2IrO4
• Persistent non-metallic behavior in Sr2IrO4 and Sr3Ir2O7 at high pressures
• All-in/all-out magnetic domains: X-ray diffraction imaging and magnetic field control
• First-order melting of a weak spin-orbit Mott insulator into a correlated metal
• Pressure-Induced Confined Metal from the Mott Insulator Sr3Ir2O7
• Electrical Control of Structural and Physical Properties via Strong Spin-Orbit Interactions in Sr2IrO4
• Structural investigation of the bilayer iridate Sr3Ir2O7
• Jahn-Teller effect in systems with strong on-site spin-orbit coupling
• First-order structural transition and pressure-induced lattice/phonon anomalies in Sr${}_2$IrO${}_4$
• Pressure dependence of the structure and electronic properties of Sr3Ir2O7

Cited by in corpus (9)

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• Symmetry-resolved two-magnon excitations in a strong spin-orbit-coupled bilayer antiferromagnet
• Octahedral tilting induced isospin reorientation transition in iridate heterostructures
• Exciton condensation in bilayer spin-orbit insulator
• Anisotropic Lattice Compression and Pressure-Induced Electronic Phase Transitions in Sr${}_2$IrO${}_4$
• Reconciling monolayer and bilayer $J_{\mathrm{eff}}=1/2$ square lattices in hybrid oxide superlattice
• Evolution of electronic and magnetic properties of Sr${}_2$IrO${}_4$ under strain
• Outstanding TC Enhancement in 5d-3d Y2NiIrO6 by Compression
• Multiple topological phases of magnons induced by Dzyaloshinskii-Moriya and pseudodipolar anisotropic exchange interactions in Kagome ferromagnets