Impurity induced magnetic ordering in Sr${}_2$RuO${}_4$

Abstract

Ti substituting Ru in Sr${}_2$RuO${}_4$ in small concentrations induces incommensurate spin density wave order with a wave vector $\mathbf{Q}\simeq (2\pi /3,2\pi /3)$ corresponding to the nesting vector of two out of three Fermi surface sheets. We consider a microscopic model for these two bands and analyze the correlation effects leading to magnetic order through non-magnetic Ti-doping. For this purpose we use a position dependent mean field approximation for the microscopic model and a phenomenological Ginzburg-Landau approach, which both deliver consistent results and allow us to examine the inhomogeneous magnetic order. Spin-orbit coupling additionally leads to spin currents around each impurity, which in combination with the magnetic polarization produce a charge current pattern. This is also discussed within a gauge field theory in both charge and spin channel. This spin-orbit coupling effect causes an interesting modification of the magnetic structure, if currents run through the system. Our findings allow a more detailed analysis of the experimental data for Sr${}_2$Ru${}_{1-x}$Ti${}_x$O${}_4$. In particular, we find that the available measurements are consistent with our theoretical predictions.

17 pages, 12 figures

References in corpus (3)

• Chiral P-Wave Order in Sr_2RuO_4
• Properties of edge states in spin-triplet two-band superconductor
• Impurity-induced bound states inside the superconducting gap of FeSe

Cited by in corpus (6)

• Revisiting superconductivity in the extended one-band Hubbard model: pairing via spin and charge fluctuations
• Superconducting gap symmetry from Bogoliubov quasiparticle interference analysis on {Sr}${}_2${RuO}${}_4$
• Negatively enhanced thermopower near a Van Hove singularity in electron-doped Sr${}_2$RuO${}_4$
• Impurity-induced spin density wave in the thermoelectric layered cobaltite [Ca${}_2$CoO${}_3$]${}_{0.62}$[CoO${}_2$]
• Unconventional superconducting correlations in fermionic many-body scars
• Certain BCS wavefunctions are quantum many-body scars