Crystal growth and intrinsic magnetic behavior of Sr${}_2$IrO${}_4$

Abstract

We report on the growth of stoichiometric Sr${}_2$IrO${}_4$ single crystals, which allow us to unveil their intrinsic magnetic properties. The effect of different growth conditions has been investigated for crystals grown by the flux method. We find that the magnetic response depends very sensitively on the details of the growth conditions. We assess the defect concentration based on magnetization, X-ray diffraction, Raman scattering, and optical conductivity measurements. We find that samples with a low concentration of electronically active defects show much reduced in-gap spectral weight in the optical conductivity and a pronounced two-magnon peak in the Raman scattering spectrum. A prolonged exposure at high temperature during the growth leads to higher defect concentration likely due to creation of oxygen vacancies. We further demonstrate a systematic intergrowth of Sr${}_2$IrO${}_4$ and Sr${}_3$Ir${}_2$O${}_7$ phases by varying the growth temperature. Our results thus emphasize that revealing the intrinsic magnetic properties of Sr${}_2$IrO${}_4$ and related materials requires a scrupulous control of the crystal growth process.

References in corpus (14)

• Mott Insulators in the Strong Spin-Orbit Coupling Limit: From Heisenberg to a Quantum Compass and Kitaev Models
• Novel Jeff = 1/2 Mott State Induced by Relativistic Spin-Orbit Coupling in Sr2IrO4
• Twisted Hubbard Model for Sr2IrO4: Magnetism and Possible High Temperature Superconductivity
• Fermi Arcs in a Doped Pseudospin-1/2 Heisenberg Antiferromagnet
• Observation of a $d$-wave gap in electron-doped Sr${}_2$IrO${}_4$
• Collapse of the Mott gap and emergence of a nodal liquid in lightly doped Sr${}_2$IrO${}_4$
• Signature of high temperature superconductivity in electron doped Sr2IrO4
• Excitonic quasiparticles in a spin-orbit Mott insulator
• Odd-parity triplet superconductivity in multi-orbital materials with strong spin-orbit coupling: applications to doped Sr2IrO4
• Spin-orbit tuned metal-insulator transitions in single-crystal Sr2Ir1-xRhxO4 (0\leqx\leq1)
• Transfer of spectral weight across the gap of Sr2IrO4 induced by La doping
• The importance of XY anisotropy in Sr2IrO4 revealed by magnetic critical scattering experiments
• Evidence for ordered magnetic moments at oxygen sites in antiferromagnetic Sr${}_2$IrO${}_4$ and Sr${}_3$Ir${}_2$O${}_7$
• Electron-Doped Sr2IrO4-delta (0 <= delta <= 0.04): Evolution of a Disordered Jeff = 1/2 Mott Insulator into an Exotic Metallic State

Cited by in corpus (29)

• Square Lattice Iridates
• Persistent paramagnons deep in the metallic phase of Sr${}_{2-x}$La${}_x$IrO${}_4$
• Giant anisotropic magnetoresistance and nonvolatile memory in canted antiferromagnet Sr2IrO4
• Two-magnon Raman scattering and pseudospin-lattice interactions in Sr2IrO4 and Sr3Ir2O7
• Pseudospin-lattice coupling in the spin-orbit Mott insulator Sr2IrO4
• Relativistic $GW$+BSE study of the optical properties of Ruddlesden-Popper iridates
• Dimensionality-strain phase diagram of strontium iridates
• Raman scattering study of vibrational and magnetic excitations in Sr${}_{2-x}$La${}_x$IrO${}_4$
• The Jeff=1/2 antiferromagnet Sr2IrO4: A golden avenue toward new physics and functions
• Spin-orbit-enhanced magnetic surface second-harmonic generation in Sr${}_2$IrO${}_4$
• Spin-gap and two-dimensional magnetic excitations in Sr2IrO4
• Evolution of remnant Fermi surface state in lightly-doped correlated spin-orbit insulator Sr${}_{2-x}$La${}_x$IrO${}_4$
• Optical anisotropy of the Jeff = 1/2 Mott insulator Sr2IrO4
• Magnetic properties of bilayer Sr${}_3$Ir${}_2$O${}_7$: role of epitaxial strain and oxygen vacancies
• Magnetization density distribution of Sr${}_2$IrO${}_4$: Deviation from a local $j_{\text{eff}}=1/2$ picture
• Structural evolution and electronic properties of (Sr1-xCax)2-yIrO4+z spin-orbit assisted insulators
• Spin-wave gap collapse in Rh-doped Sr2IrO4
• Compressive-strain induced enhancement of exchange interactions and short-range magnetic order in Sr${}_2$IrO${}_4$ investigated by Raman spectroscopy
• Unusual slow magnetic fluctuations and critical slowing down in Sr${}_2$Ir${}_{1-x}$Rh${}_x$O${}_4$
• Nonsymmorphic Dirac semimetal and carrier dynamics in doped spin-orbit-coupled Mott insulator Sr${}_2$IrO${}_4$
• Direct observation of oxygen polarization in Sr${}_2$IrO${}_4$ by O $K$-edge x-ray magnetic circular dichroism
• Precise control of $J_{\mathrm{eff}}=1/2$ magnetic properties in Sr${}_2$IrO${}_4$ epitaxial thin films by variation of strain and thin film thickness
• Single crystal growth of iridates without platinum impurities
• Flux growth of Sr(n+1)Ir(n)O(3n+1) [n=1, 2, infinity] crystals
• Magneto-synthesis effect on magnetic order, phonons, and magnons in single-crystal Sr${}_2$IrO${}_4$
• Quantum Criticality in a Layered Iridate
• Structural origin of the Jeff=1/2 antiferromagnetic phase in Ga-doped Sr2IrO4
• High-pressure floating zone crystal growth of Sr${}_2$IrO${}_4$
• Absence of temperature-dependent phonon anomalies in Sr2IrO4 and Sr3Ir2O7