Some peculiarities of labile oxygen kinetics in underdoped single crystals of YBa2Cu3O7-x

We study the time dependence of the electrical conductivity of single-crystalline YBa2Cu3O7-x with varying oxygen content. We show that the accelerated transport of the oxygen ions in the initial stage of the process occurs along one-dimensional clusters of nonstoichiometric vacancies through the single-file diffusion mechanism. The final stage of the oxygen ion redistribution in the studied compound is described with a classical mechanism of bulk diffusion. At the same time, the degree of deviation from the oxygen stoichiometry significantly influences the change in duration of the time intervals corresponding to the mechanisms of single-file and bulk diffusion of the labile oxygen.