A definitive study of the spin density wave ordering in the high temperature Nickelate superconductor, La3Ni2O7

The recent discovery of superconductivity in Ruddlesden-Popper phase lanthanum nickelates, particularly La₃Ni₂O₇ has revitalised interest in high-temperature superconductors. La₃Ni₂O₇ exhibits superconductivity at 80 K under uniaxial pressure (15–40 GPa), and subsequent studies have identified a charge density wave, potentially a precursor to superconductivity, in both pressurised and ambient conditions. Recent reports of the magnetic structure of La₃Ni₂O₇ are ambiguous and contradicting. In light of these unresolved magnetic structure of the spin density wave ordering, we propose to investigate La₃Ni₂O₇ using the WISH instrument at ISIS using our good quality single crystals and powder samples. WISH’s high flux, excellent resolution, and low background make it essential for detailed crystallographic and magnetic studies of these materials. We request two days of Rapid Access beamtime for neutron diffraction measurements on to fully determine the magnetic structure using our already tested La₃Ni₂O₇ samples.