µSR study on the parent material RNiO2 (R= La, Nd) of new nickelate superconductors

Superconductivity with the critical temperature up to 15 K is indeed discovered in Nd0.8Sr0.2NiO2, suggesting the possibility of a family of nickelate superconductors analogous to copper oxides and pnictides. To elucidate the precise relationship between nickelate superconductors and other high Tc superconductors, and the origin of superconductivity in nickelate, the studies on the parent material NdNiO2 are necessary. We propose to perform muon spin relaxation experiments to check whether there exists long-range magnetic order or magnetic fluctuations on Ni sites in NdNiO2 and LaNiO2. The success of the experiments will give strong evidence about whether the superconductivity in Nd0.8Sr0.2NiO2 is related to magnetism, as in high Tc curates and other unconventional superconductors.