Magnetic Excitations in Parent Compounds of Nickelate Superconductors

The discovery of the superconductivity in cuprates has motivated the study of compounds with similar structures aiming to find new superconductors and understand the microscopic origin of the unconventional superconductivity. In general, superconductivity in cuprates is believed to arise from spin fluctuations, which play a critical role in mediating the electrons to form Cooper pairs. Following the approach to study isostructural compounds of cuprates, superconductivity is reported in soft-chemistry topotactic reduced NdNiO2 and Nd0.8Sr0.2NiO2 thin films, indicating possible series of superconductors based on reduced layered nickelate structure. We propose to perform an inelastic neutron scattering experiment on MERLIN to determine the magnetic excitations in tri-layer nickelate compounds Nd4Ni3O8 and Nd4Ni3O10, and infinite-layer nickelate compound NdNiO2 with poly-crystalline samples.