Abstract
Dynamical structures in the vicinity of Q = (π, π) of optimally-doped YBa2Cu3O6.9 were measured by means of an inelastic neutron scattering technique utilizing pulsed neutron source. Obtained incommensurability δ of energy transfer at E = 36 meV was found to be ∼0.1 [rlu] which is not the value to be expected from the formation of spin-charge stripes. In higher energy above resonance energy (42 meV), a ring structure centered at (π, π) was observed up to 54 meV. Combined with the low energy part of the dynamical structure, the obtained results provide a total picture of the dynamical aspects in the high-Tc superconductor YBa2Cu3O6.9.