Thermal neutron three-axis spectrometer with polarization analysis

Anisotropy of the magnetic incommensurate fluctuations

The unconventional superconductor Sr2RuO4 is isostructural with the high-Tc superconductor La2-xSrxCuO4 (LSCO) but exhibits an unusual triplet (p-wave) spin-pairing.

Polarisation analysis on IN20 provides a tool to probe theoretical models requiring the presence of (quasi-)ferromagnetic or highly anisotropic antiferromagnetic fluctuations in the neutron response.

The present IN20 results confirm the latter scenario qualitatively, with incommensurate fluctuations (similar to those observed in LSCO), whose anisotropy between the in-plane (χ"ab) and out-of-plane (χ"c) components and energy dependence are weaker than predicted for p-wave pairing.