The spin liquid state in the hole-doped two-leg ladder system (Sr2.5Ca11.5)Cu24O41which exhibits unique superconductivity under high pressure, has been studied by neutron inelastic scattering at ambient pressure. The spin gap energy for the ladder is found to be 32.1±0.3meV, which is still almost the same as that of the parent material Sr14Cu24O41. From the observed dispersion relation, the exchange coupling is roughly estimated at J∥∼90±15meV (along the ladders) and J⊥∼65±10meV(along the rungs). The coupling constant J? is slightly decreased from that obtained for the parent compound.
ASJC Scopus subject areas
- Physics and Astronomy(all)