Magnetic reorientation transition in a three orbital model for $\mathrm{C}{\mathrm{a}}_2\mathrm{Ru}{\mathrm{O}}_4$ -- Interplay of spin-orbit coupling, tetragonal distortion, and Coulomb interactions

Abstract

Including the orbital off-diagonal spin and charge condensates in the self consistent determination of magnetic order within a realistic three-orbital model for the $4d^4$ compound $\mathrm{C}{\mathrm{a}}_2\mathrm{Ru}{\mathrm{O}}_4$, reveals a host of novel features including strong and anisotropic spin-orbit coupling (SOC) renormalization, coupling of strong orbital magnetic moments to orbital fields, and a magnetic reorientation transition. Highlighting the rich interplay between orbital geometry and overlap, spin-orbit coupling, Coulomb interactions, tetragonal distortion, and staggered octahedral tilting and rotation, our investigation yields a planar antiferromagnetic (AFM) order for moderate tetragonal distortion, with easy $a-b$ plane and easy $b$ axis anisotropies, along with small canting of the dominantly $yz,xz$ orbital moments. With decreasing tetragonal distortion, we find a magnetic reorientation transition from the dominantly planar AFM order to a dominantly $c$ axis ferromagnetic (FM) order with significant $xy$ orbital moment.

28 pages, 9 figures

References in corpus (8)

• Novel Jeff = 1/2 Mott State Induced by Relativistic Spin-Orbit Coupling in Sr2IrO4
• Subband filling and Mott transition in Ca_{2-x}Sr_xRuO_4
• Lattice-Tuned Magnetism of Ru4+(4d4) Ions in Single-Crystals of the Layered Honeycomb Ruthenates: Li2RuO3 and Na2RuO3
• Observation of spin-orbit excitations and Hund's multiplets in Ca${}_2$RuO${}_4$
• Magnetic Excitations in Spin-Orbit Coupled $d^4$ Mott Insulator on Square Lattice
• Tailoring the electronic properties of Ca${}_2$RuO${}_4$ via epitaxial strain
• Density matrix renormalization group study of a three-orbital Hubbard model with spin-orbit coupling in one dimension
• Correlated motion of particle-hole excitations across the renormalized spin-orbit gap in $\mathrm{S}{\mathrm{r}}_2\mathrm{Ir}{\mathrm{O}}_4$

Cited by in corpus (7)

• Strain control of a bandwidth-driven spin reorientation in Ca${}_3$Ru${}_2$O${}_7$
• Spin-orbit coupling and crystal-field splitting in Ti-doped Ca2RuO4 studied by ellipsometry
• Magnetic phases for two $t_{2g}$ holes with spin-orbit coupling and crystal field
• Pseudo-spin rotation symmetry breaking by Coulomb interaction terms in spin-orbit coupled systems
• Time-hidden magnetic order in a multi-orbital Mott insulator
• 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 $\mathrm{S}{\mathrm{r}}_2\mathrm{Ir}{\mathrm{O}}_4$
• Collective mode excitations and simulated $L$-edge resonant-inelastic x-ray scattering spectra in antiferromagnetic Ca${}_2$RuO${}_4$