The existing measurements of elastic energy dissipation and modulus on RBa2Cu3O6+x have been reviewed and the possible mechanisms have been discussed taking into account the whole range of temperatures and O stoichiometries. Most of the processes have been correlated with the dynamics of O in the CuOx planes: those above room temperature to jumps of O bound in chains and ordered domains, and those at low temperature with hops between off-centre positions within the chains. Free oxygen in the diluted tetragonal phase has a mobility which is anomalously high for an oxide. Phase transformations are observed both above and below room temperature, and have been discussed in connection with the relaxation processes.
Dynamics of oxygen and phase transitions in the 123 ceramic superconductors by anelastic relaxation measurements
F Cordero;
1992
Abstract
The existing measurements of elastic energy dissipation and modulus on RBa2Cu3O6+x have been reviewed and the possible mechanisms have been discussed taking into account the whole range of temperatures and O stoichiometries. Most of the processes have been correlated with the dynamics of O in the CuOx planes: those above room temperature to jumps of O bound in chains and ordered domains, and those at low temperature with hops between off-centre positions within the chains. Free oxygen in the diluted tetragonal phase has a mobility which is anomalously high for an oxide. Phase transformations are observed both above and below room temperature, and have been discussed in connection with the relaxation processes.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
