Polarized and unpolarized neutron scattering have been used to determine the effect of superconductivity on the magnetic excitation spectra of YBa2Cu3O6.5 (Tc = 52K) and YBa2Cu3O6.7 (Tc = 67K). Pronounced enhancements of the spectral weight centered around 25 and 33 meV, respectively, are observed below Tc in both crystals, compensated predominantly by a loss of spectral weight at higher energies. The data provide important clues to the origin of the 40 meV magnetic resonance peak in YBa2Cu3O7.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)