Anelastic Relaxation Of Oxygen Vacancies And High-Tc Superconductivity Of Yba2cu3o7-Delta

It is suggested that the variation of the internal friction (IF) characteristics of a single-phase YBCO specimen resulting from an increase of oxygen deficiency δ is associated either with an order diffusion process between layers, or with an order/disorder diffusion process in the Cu(2) plane. The experimental results are explained in the light of these oxygen-vacancy migration processes. The essential connections between high-Tc superconductivity, electric behaviour and oxygen-vacancy ordering are discussed.