Orbital ordering transition in Ca${}_2$RuO${}_4$ observed with resonant x-ray diffraction

Abstract

Resonant x-ray diffraction performed at the ${\mathrm{L}}_{\mathrm{II}}$ and ${\mathrm{L}}_{\mathrm{III}}$ absorption edges of Ru has been used to investigate the magnetic and orbital ordering in Ca${}_2$RuO${}_4$ single crystals. A large resonant enhancement due to electric dipole $2p\to 4d$ transitions is observed at the wave-vector characteristic of antiferromagnetic ordering. Besides the previously known antiferromagnetic phase transition at ${\mathrm{T}}_{\mathrm{N}}=110$ K, an additional phase transition, between two paramagnetic phases, is observed around 260 K. Based on the polarization and azimuthal angle dependence of the diffraction signal, this transition can be attributed to orbital ordering of the Ru $t_{2g}$ electrons. The propagation vector of the orbital order is inconsistent with some theoretical predictions for the orbital state of Ca${}_2$RuO${}_4$.

to appear in PRL

References in corpus (8)

• Structural and magnetic aspects of the metal insulator transition in Ca${}_{2-x}$Sr${}_x$RuO${}_4$
• Destruction of the Mott Insulating Ground State of Ca_2RuO_4 by a Structural Transition
• Orbital Dependent Phase Control in Ca2-xSrxRuO4
• Soft x-ray resonant diffraction study of magnetic and orbital correlations in a manganite near half-doping
• Resonant x-ray diffraction study of the magnetoresistant perovskite Pr0.6Ca0.4MnO3
• Prediction of Orbital Ordering in Single-Layered Ruthenates
• Electron and orbital correlations in Ca_{2-x}Sr_{x}RuO_{4} probed by optical spectroscopy
• Filling Control of the Mott Insulator Ca2RuO4

Cited by in corpus (42)

• Anomalous Antiferromagnetism in Metallic RuO${}_2$ Determined by Resonant X-ray Scattering
• Nature of the Mott transition in Ca2RuO4
• Orbital ordering phenomena in $d$- and $f$-electron systems
• Coulomb-Enhanced Spin-Orbit Splitting: The Missing Piece in the Sr2RhO4 Puzzle
• Neutron diffraction study of YVO3, NdVO3, and TbVO3
• Pseudo Jahn-Teller Effect and Magnetoelastic Coupling in Spin-Orbit Mott Insulators
• Current-Induced Gap Suppression in the Mott Insulator Ca${}_2$RuO${}_4$
• Spin-Orbit-Induced Orbital Excitations in Sr2RuO4 and Ca2RuO4: A Resonant Inelastic X-ray Scattering Study
• Metal-Insulator Transition and Orbital Order in PbRuO3
• Current-induced giant diamagnetism in the Mott insulator Ca2RuO4
• Magnetic Anisotropy and Orbital Ordering in Ca${}_2$RuO${}_4$
• Tailoring the electronic properties of Ca${}_2$RuO${}_4$ via epitaxial strain
• Nonequilibrium Orbital Transitions via Applied Electrical Current in Calcium Ruthenate
• Unusual heavy-mass nearly ferromagnetic state with a surprisingly large Wilson ratio in the double layered ruthenates (Sr${}_{1-x}$Ca${}_x$)${}_3$Ru${}_2$O${}_7$
• Magnetic structure of RuSr${}_2$GdCu${}_2$O${}_8$ determined by resonant x-ray diffraction
• Raman scattering from current-stabilized nonequilibrium phases in Ca${}_2$RuO${}_4$
• Strain-induced orbital energy shift in antiferromagnetic RuO2 revealed by resonant elastic x-ray scattering
• Excitonic Magnetism at the intersection of Spin-orbit coupling and crystal-field splitting
• Existence of electron and hole pockets and partial gap opening in the correlated semimetal Ca3Ru2O7
• Role of local temperature in the current-driven metal-insulator transition of Ca2RuO4
• Microscopic theory of resonant soft x-ray scattering in systems with charge order
• Van Vleck excitons in Ca${}_2$RuO${}_4$
• Tuning of the Ru${}^{4+}$ ground-state orbital population in the $4{\mathbf{d}}^4$ Mott insulator Ca${}_2$RuO${}_4$ achieved by La doping
• Persistence of antiferromagnetic order upon La substitution in the $4d^4$ Mott insulator Ca${}_2$RuO${}_4$
• Quest for New Quantum States via Field-Editing Technology
• Complex electronic states in double layered ruthenates (Sr1-xCax)3Ru2O7
• Abnormal $phase$ flip in coherent phonon oscillations of Ca${}_2$RuO${}_4$
• Direct observation of electron density reconstruction at the metal-insulator transition in NaOsO3
• Towards Electrical-Current Control of Quantum States in Spin-Orbit-Coupled Matter
• A coherent phonon-induced hidden quadrupolar ordered state in Ca${}_2$RuO${}_4$
• Suppression of effective spin-orbit coupling by thermal fluctuations in spin-orbit coupled antiferromagnets
• Hidden Phases Revealed at the Surface of Double-Layered Sr3(Ru1-xMnx)2O7
• Spin polarization of Ru in superconducting Ba(Fe${}_{0.795}$Ru${}_{0.205}$)${}_2$As${}_2$ studied by x-ray resonant magnetic scattering
• Spin-orbit coupling and crystal-field splitting in Ti-doped Ca2RuO4 studied by ellipsometry
• The Iso-electronic Series $C{a}_{2-x}S{r}_{x}Ru{O}_4$: Structural Distortion, Effective Dimensionality, Spin Fluctuations and Quantum Criticality
• Magnetic phases for two $t_{2g}$ holes with spin-orbit coupling and crystal field
• Evidence of structural evolution in Sr2RhO4 studied by time-resolved optical reflectivity spectroscopy
• Time-hidden magnetic order in a multi-orbital Mott insulator
• Critical magnetic fluctuations in the layered ruthenates Ca${}_2$RuO${}_4$ and Ca${}_3$Ru${}_2$O${}_7$
• Ultrafast signatures of spin and orbital order in antiferromagnetic $\alpha$-Sr${}_2$CrO${}_4$
• Unique Itinerant Ferromagnetism in 4d-electron System Ca2RuO4
• Universal size-dependent nonlinear charge transport in single crystals of the Mott insulator Ca${}_2$RuO${}_4$