We have performed inelastic neutron scattering on a single crystal sample of Sr14Cu24O41 to study the spin dynamics of the Cu2O3 spin ladder layers and CuO2 chains. Our data are best fitted with a dispersion which has a spin gap of 32.5±0.1meV and a maximum of 193.5±2.4meV, consistent with a coupling along the ladders, J∥=130 meV and a rung coupling J⊥ = 72 meV. Excitations with an energy transfer of approximately 11.5 meV arise from a dimer chain with an antiferromagnetic intradimer coupling J1=11.2meV between next-nearest-neighbor Cu ions, and a ferromagnetic interdimer coupling J2=−1.1meV. The dimer chains have a periodicity of five units.
ASJC Scopus subject areas
- Physics and Astronomy(all)