Superionic behavior of high-temperature superconductors

Abstract
Ionic transport, a characteristic feature of superionic conductors, is analyzed microscopically for the RBa2 Cu3 O7δf(R=rare earth) high-temperature superconductors. The electronic correlation effects are considered to be responsible for the formation of a local double-well potential for apical oxygen, which, in turn, results in a decrease of the activation energy for interstitial chain oxygen defects.