Temperature-dependent neutron-scattering measurements of the dynamic susceptibility χ''(ω) in single-crystal YBa2Cu3O6.6 (Tc=53 K) are reported. At high temperatures (T100 K) a universal dependence of χ''(ω) on the ratio ω/T has been observed. A spin pseudogap ωg10 meV results in a breakdown in this behavior at temperatures well above Tc. Below ∼40 K the scattering intensities at energy transfers of ΔE=5 and 8 meV demonstrate a surprising recovery with decreasing temperature. The behavior of χ''(ω) over the range of energies (3-16 meV) and temperatures (1.5-300 K) studied presents a strong constraint on theoretical descriptions of YBa2Cu3O6+x.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics