Frustrated Ising chains on the triangular lattice in Sr 3 NiIrO 6

摘要: Inelastic neutron scattering study on the spin-chain compound ${\mathrm{Sr}}_{3}{\mathrm{NiIrO}}_{6}$ reveals gapped quasi-1D magnetic excitations. The observed one-magnon band between 29.5 and 39 meV consists of magnon modes ${\mathrm{Ni}}^{2+}$ ions. fitting spin wave spectrum strongly coupled Ising-like chains along $c$ axis that are weakly into a frustrated triangular lattice in $ab$ plane. excitations survive up to 200 K well above ordering temperature ${T}_{N}\ensuremath{\sim}75$ K, also indicating nature interactions ${\mathrm{Sr}}_{3}{\mathrm{NiIrO}}_{6}$. Our microscopic model is agreement with ab initio electronic structure calculations explains giant spin-flip field bulk magnetization measurements.