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Incommensurate magnetic ordering in Sr_2Ru_(1-x)Ti_xO_4

M. Braden·O. Friedt·Y. Sidis·P. Bourges·M. Minakata·Y. Maeno
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Abstract

In $\rm Sr_2RuO_4$ the spin excitation spectrum is dominated by incommensurate fluctuations at q=(0.3 0.3 q$_z$), which arise from Fermi-surface nesting. We show that upon Ti substitution, known to suppress superconductivity, a short range magnetic order develops with a propagation vector (0.307 0.307 1). This finding confirms that superconducting $\rm Sr_2RuO_4$ is extremely close to an incommensurate spin density wave instability. In addition, the ordered moment in \srton ~ points along the c-direction, which indicates that the incommensurate spin fluctuations exhibit the anisotropy required to explain a p-wave spin triplet pairing.

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M. Braden, O. Friedt, Y. Sidis, P. Bourges, M. Minakata, Y. Maeno. 2001-07-30. Incommensurate magnetic ordering in Sr_2Ru_(1-x)Ti_xO_4. https://doi.org/10.1103/physrevlett.88.197002

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