Description
Abstract: Pressurized Ruddlesden–Popper nickelates have recently emerged as a new family of high-T꜀ superconductors. The trilayer member La₄Ni₃O₁₀ becomes superconducting near 30 K under pressure, while at ambient pressure it hosts an intertwined density-wave order. As in the cuprates, the magnetism of this parent phase is widely believed to be intimately tied to electron pairing, yet the momentum- and energy-resolved spin correlations of La₄Ni₃O₁₀ have yet to be fully resolved.. Here we use inelastic neutron scattering (INS) on co-aligned single crystals to map the spin excitations of trilayer La₄Ni₃O₁₀ across the Brillouin zone. Within a local-moment picture, the measured dispersions and intensities are well reproduced, to a good approximation, by a Heisenberg model evaluated using linear spin-wave theory (SpinW), from which we extract the dominant magnetic exchange interactions. Combined with absolute-unit normalization, this analysis yields the effective magnetic exchange Hamiltonian and the total fluctuating moment of the system.
