Orbital Properties of Sr3Ru2O7 and Related Ruthenates Probed by 17O-NMR

Abstract

We report a site-separated ${}^{17}$O-NMR study of the layered perovskite ruthenate Sr${}_3$Ru${}_2$O${}_7$, which exhibits nearly two-dimensional transport properties and itinerant metamagnetism at low temperatures. The local hole occupancies and the spin densities in the oxygen $2p$ orbitals are obtained by means of tight-binding analyses of electric field gradients and anisotropic Knight shifts. These quantities are compared with two other layered perovskite ruthenates: the two-dimensional paramagnet Sr${}_2$RuO${}_4$ and the three-dimensional ferromagnet SrRuO${}_3$. The hole occupancies at the oxygen sites are very large, about one hole per ruthenium atom. This is due to the strong covalent character of the Ru-O bonding in this compound. The magnitude of the hole occupancy might be related to the rotation or tilt of the RuO${}_6$ octahedra. The spin densities at the oxygen sites are also large, 20-40% of the bulk susceptibilities, but in contrast to the hole occupancies, the spin densities strongly depend on the dimensionality. This result suggests that the density-of-states at the oxygen sites plays an essential role for the understanding of the complex magnetism found in the layered perovskite ruthenates.

arXiv comment9 pages, 5 figures, to be published in Phys. Rev. B

References in corpus (16)

• Transport Properties, Thermodynamic Properties, and Electronic Structure of SrRuO3
• Electronic structure and magnetism in Ru based perovskites
• Metamagnetism and critical fluctuations in high quality single crystals of the bilayer ruthenate Sr3Ru2O7
• Evidence for incommensurate spin fluctuations in Sr_2RuO_4
• The ground state of Sr3Ru2O7 revisited; Fermi liquid close to a ferromagnetic instability
• Metamagnetic Quantum Criticality
• Angular dependence of the magnetic susceptibility in the itinerant metamagnet Sr3Ru2O7
• Electronic Structure and Fermiology of Sr${}_3$Ru${}_2$O${}_7$
• Multiple first-order metamagnetic transitions and quantum oscillations in ultrapure
• Systematic approach to the growth of high-quality single-crystals of Sr3Ru2O7
• Uniaxial-Pressure induced Ferromagnetism of Enhanced Paramagnetic Sr3Ru2O7
• Metamagnetic Quantum Criticality Revealed by 17O-NMR in the Itinerant Metamagnet Sr3Ru2O7
• The de Haas-van Alphen effect across the metamagnetic transition in Sr${}_3$Ru${}_2$O${}_7$
• Anomalous spin density distribution on oxygen and Ru in Ca${}_{1.5}$Sr${}_{0.5}$RuO${}_4$: A polarised neutron diffraction study
• Investigation into the Itinerant metamagnetism of Sr3Ru2O7 for the Field Parallel to the Ruthenium Oxygen Planes
• Electric field gradients from first-principles and point-ion calculations

Cited by in corpus (1)

• Spin-orbit Coupling and Multiple Phases in Spin-triplet Superconductor Sr${}_2$RuO${}_4$