Spin excitations in nickelate superconductors

TL;DR

This paper theoretically investigates spin excitations in nickelate superconductors, revealing incommensurate and resonance phenomena, and compares these features with cuprates, providing predictions for future neutron scattering experiments.

Contribution

The study introduces a theoretical analysis of spin excitations in nickelates using a single-band model and RPA, highlighting unique incommensurate and resonance behaviors.

Findings

Spin excitations are incommensurate at low energies.

A spin resonance appears at higher energies.

The intensity peak varies with out-of-plane momentum.

Abstract

We study theoretically spin excitations in the newly discovered nickelate superconductors based on a single-band model and the random phase approximation. The spin excitations are found to be incommensurate in a low energy region. A spin resonance phenomena is revealed as the excitation energy increases. The maximum intensity may be at the incommensurate momentum or the commensurate momentum, depending on the out-of-plane momentum. The spin excitations become incommensurate again at higher energies. The similarities and differences of the spin excitations between nickelate and cuprate superconductors are addressed. Our predicted results can be tested by inelastic neutron scattering experiments later.