High pressure-induced relaxation of electrical resistance in weakly doped НоBa2Cu3O7–x single crystals

The relaxation of high-temperature resistance, ρ(300 K t), in HoBa2Cu3O7–x single crystals after a sharp change in hydrostatic pressure is investigated. A comparison of the electrical resistance relaxation against the relaxation of the superconducting transition critical temperature Тс under the same experimental conditions points to the existence of anisotropy in vacancy cluster relaxation: cluster coalescence is dominant in the Сu–О planes; however, the generation of new clusters and coalescence of existing clusters both occur in the sample volume.