Incommensurate magnetic ordering in Sr2Ru1-xTixO4 -: art. no. 197002

In Sr2RuO4 the spin excitation spectrum is dominated by incommensurate fluctuations at q=(0.3 0 .3q(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). In Sr2Ru0.91Ti0.09O4 , the ordered moment points along the c direction. This finding shows that superconducting Sr2RuO4 is extremely close to an incommensurate spin density wave instability.