Square Lattice Iridates

Abstract

Over the last few years, Sr${}_2$IrO${}_4$, a single-layer member of the Ruddlesden-Popper series iridates, has received much attention as a close analog of cuprate high-temperature superconductors. Although there is not yet firm evidence for superconductivity, a remarkable range of cuprate phenomenology has been reproduced in electron- and hole-doped iridates including pseudogaps, Fermi arcs, and $d$-wave gaps. Further, a number of symmetry breaking orders reminiscent of those decorating the cuprate phase diagram have been reported using various experimental probes. We discuss how the electronic structures of Sr${}_2$IrO${}_4$ through strong spin-orbit coupling leads to the low-energy physics that had long been unique to cuprates, what the similarities and differences between cuprates and iridates are, and how these advance the field of high-temperature superconductivity by isolating essential ingredients of superconductivity from a rich array of phenomena that surround it. Finally, we comment on the prospect of finding a new high-temperature superconductor based on the iridate series.

Annu. Rev. Condens. Matter Phys. (in press)

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• On the magnetic structure of Sr3Ir2O7: an x-ray resonant scattering study
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Cited by in corpus (68)

• Spin-orbit-entangled electronic phases in 4$d$ and 5$d$ transition-metal compounds
• Beyond-classical computation in quantum simulation
• Landscape of competing stripe and magnetic phases in cuprates
• Pseudo Jahn-Teller Effect and Magnetoelastic Coupling in Spin-Orbit Mott Insulators
• Pseudospin-lattice coupling in the spin-orbit Mott insulator Sr2IrO4
• Observation of spin-orbit excitations and Hund's multiplets in Ca${}_2$RuO${}_4$
• Cavity magnon-polaritons in cuprate parent compounds
• The Jeff=1/2 antiferromagnet Sr2IrO4: A golden avenue toward new physics and functions
• Review on quasi-2D square planar nickelates
• First-Principles Calculation of Spin and Orbital Contributions to Magnetically Ordered Moments in Sr${}_2$IrO${}_4$
• Correlated Quantum Phenomena of Spin-Orbit Coupled Perovskite Oxide Heterostructures: Cases of SrRuO3 and SrIrO3-Based Artificial Superlattices
• Strange semimetal dynamics in SrIrO${}_3$
• Possible quantum paramagnetism in compressed Sr${}_2$IrO${}_4$
• Quantum spin nematic phase in a square-lattice iridate
• Bond Directional Anapole Order in a Spin-Orbit Coupled Mott Insulator Sr${}_2$(Ir${}_{1-x}$Rh${}_x$)O${}_4$
• Strain-modulated Slater-Mott crossover of pseudospin-half square-lattice in (SrIrO3)1/ (SrTiO3)1 superlattices
• Toward cubic symmetry for Ir${}^{4+}$: structure and magnetism of antifluorite K${}_2$IrBr${}_6$
• Excitonic Magnetism at the intersection of Spin-orbit coupling and crystal-field splitting
• Magnetization density distribution of Sr${}_2$IrO${}_4$: Deviation from a local $j_{\text{eff}}=1/2$ picture
• How spin-orbital entanglement depends on the spin-orbit coupling in a Mott insulator
• Spin-orbit effects in pentavalent Iridates: Models and materials
• Comprehensive Control of Metamagnetic Transition of Antiferromagnetic Mott Insulator Sr2IrO4 by in-situ Anisotropic Strain
• Anomalous Magnetoresistance due to Longitudinal Spin Fluctuations in a Jeff = 1/2 Mott Semiconductor
• Spin-wave gap collapse in Rh-doped Sr2IrO4
• Anapole Correlations in Sr2IrO4 Defy the jeff = 1/2 Model
• Imaging antiferromagnetic domain fluctuations and the effect of atomic-scale disorder in a doped spin-orbit Mott insulator
• Orbital Symmetry and Orbital Excitations in High-$T_c$ Superconductors
• Random singlet state in Ba${}_5$CuIr${}_3$O${}_{12}$ single crystals
• Magnetism and metal-insulator transitions in the Rashba-Hubbard model
• Sr${}_2$IrO${}_4$/Sr${}_3$Ir${}_2$O${}_7$ superlattice for a model 2D quantum Heisenberg antiferromagnet
• Antiferromagnetic Chern insulator in centrosymmetric systems
• Phonon spectrum of Pr${}_2$Zr${}_2$O${}_7$ and Pr${}_2$Ir${}_2$O${}_7$ as an evidence of coupling of the lattice with electronic and magnetic degrees of freedom
• Odd-Parity Superconductivity Driven by Octahedra Rotations in Iridium Oxides
• Structural and Magnetic Transitions in the Planar Antiferromagnet Ba${}_4$Ir${}_3$O${}_{10}$
• Controllable emergent spatial spin modulation in Sr2IrO4 by in situ shear strain
• Direct observation of oxygen polarization in Sr${}_2$IrO${}_4$ by O $K$-edge x-ray magnetic circular dichroism
• Exciton condensation in bilayer spin-orbit insulator
• Strain tuned magnetotransport of Jeff=1/2 antiferromagnetic Sr2IrO4 thin films
• Non-thermal breaking of magnetic order via photo-generated spin defects
• Momentum-resolved lattice dynamics of parent and electron-doped Sr${}_2$IrO${}_4$
• Unconventional anomalous Hall effect in epitaxially stabilized orthorhombic Ru${}^{3+}$ perovskite thin films
• Flux growth of Sr(n+1)Ir(n)O(3n+1) [n=1, 2, infinity] crystals
• IrF4: From Tetrahedral Compass Model to Topological Semimetal
• Strain-induced superconductivity in Sr2IrO4
• Quasi-2D anomalous Hall Mott insulator of topologically engineered Jeff =1/2 electrons
• Carrier density crossover and quasiparticle mass enhancement in a doped 5$d$ Mott insulator
• Single crystal growth of iridates without platinum impurities
• Magnetism-Enhanced Strong Electron-Phonon Coupling in Infinite-Layer Nickelate
• Magnetic phases for two $t_{2g}$ holes with spin-orbit coupling and crystal field
• Ground state properties of the Heisenberg-compass model on the square lattice
• Magnon Spectra of Cuprates beyond Spin Wave Theory
• Modeling multiorbital effects in Sr2IrO4 under strain and a Zeeman field
• Weyl semimetallic state with antiferromagnetic order in Rashba-Hubbard model
• Reconciling monolayer and bilayer $J_{\mathrm{eff}}=1/2$ square lattices in hybrid oxide superlattice
• Theoretical analysis of multi-magnon excitations in resonant inelastic x-ray scattering spectra of two-dimensional antiferromagnets
• Coupled spin-orbital fluctuations in a three orbital model for $4d$ and $5d$ oxides with electron fillings $n=3,4,5$ -- Application to $\mathrm{NaOs}{\mathrm{O}}_3$, $\mathrm{C}{\mathrm{a}}_2\mathrm{Ru}{\mathrm{O}}_4$, and $\mathrm{S}{\mathrm{r}}_2\mathrm{Ir}{\mathrm{O}}_4$
• Pseudo-spin rotation symmetry breaking by Coulomb interaction terms in spin-orbit coupled systems
• Exact Ground States and Phase Diagram of the Quantum Compass Model under an in-plane Field
• Momentum space imaging of locally noncentrosymmetric superconductors
• Symmetry breaking and competing valence bond states in the star lattice Heisenberg antiferromagnet
• Epitaxial growth and antiferromagnetism of Sn-substituted perovskite iridate SrIr${}_{0.8}$Sn${}_{0.2}$O${}_3$
• The rich phase diagram of the prototypical iridate Ba${}_2$IrO${}_4$: Effective low-energy models and metal-insulator transition
• Anisotropy of Antiferromagnetic Domains in a Spin-orbit Mott Insulator
• Spin and charge order in doped spin-orbit coupled Mott insulators
• Three-dimensional Stacking of Canted Antiferromagnetism and Pseudospin Current in Undoped Sr${}_2$IrO${}_4$: Symmetry Analysis and Microscopic Model Realization
• Microscopic model realization of $\mathbf{d}$-wave pseudospin current order in Sr${}_2$IrO${}_4$
• Construction of the spectral function from non-commuting spectral moment matrices
• Phase diagram and Ashkin-Teller universality in the classical square-lattice Heisenberg-compass model