Paramagnetism effect in crystals YBaCuO, generated by high-energy particles radiation

Crystals YBaCuO, having structural malformations generated due to the difference in growing conditions at the Russian Academy of Sciences (Moscow), Clarendon Laboratory (Oxford), Argonne National Laboratory and Illinois University (USA), were investigated. It was shown that only gamma-radiation, under temperature of 80 K, results in a bias of superconducting junction at 0,3-1,5 K downwards, when the dose rate increases. It indicates localization of charges in the malformations of the oxygen sublattice. Measurements by high-field SKVID-magnetometer, used for crystals and ceramics irradiated by gamma-radiation, did not reveal centers of 10-50 ke magnetic field pinning. After irradiation of YBaCuO crystals at electron accelerator with the energy of 1 MeV and fluence of 1-2·1019 cm-2, and by fast neutrons with the fluence of 1-5·1017cm-2, under temperature of 350 K, there is development of malformations both in anion and cation sublattices. Moreover, geometric malformations impact on the pinning centers. Coagulation of paramagnetic centers, near defective Cu O-clusters, intensifies the pinning process, and the healing of a part of oxygen vacancies mitigates it