Charge and Spin Order Dichotomy in NdNiO2 Driven by the Capping Layer

Charge and Spin Order Dichotomy in NdNiO₂ Driven by the Capping Layer

Superconductivity in infinite-layer nickelates holds exciting analogies with that of cuprates, with similar structures and 3d-electron count. Using resonant inelastic x-ray scattering, we studied electronic and magnetic excitations and charge density correlations in Nd_1-xSr_xNiO₂; thin films with and without SrTiO₃ capping layer. We observe dispersing magnons only in the capped samples, progressively dampened at higher doping. We detect an elastic resonant scattering peak in the uncapped compound at wave vector (∼1/3,0), remindful of the charge order signal in hole doped cuprates. The peak weakens at x=0.05 and disappears in the superconducting x=0.20 film. The role of the capping on the electronic reconstruction far from the interface remains to be understood.

Phys. Rev. Lett. 129, 027002