Features of oxygen and its vacancies diffusion in YBa2Cu3O7-{\delta}   thin films near to magnetic quantum lines
  The temperature dependence of the real and imaginary parts of magnetic susceptibility of YBa2Cu3O7-{\delta} superconducting thin films were researched at the electron irradiation with the energy of 2{\cdot}10<4> eV in the magnetic field of -2.4{\cdot}10<4> A/m at the temperature T=77 K. It is retrieved that the nonequilibrium distribution of atoms of oxygen, originating at the operation of an electron beam, reduces in the change of a sort of dependence of the complex magnetic susceptibility of YBa2 Cu3O7-{\delta} thin films on the temperature T. The diffusion relaxation of a none equilibrium distribution of oxygen atoms and its vacancies, generated at the application of electron irradiation, results in an appearance of pinning centers with the reduced contents of the oxygen in the normal cores of the Abricosov magnetic vortices. The increase of pinning forces results in the increase of critical current density, having an effect on the magnetic susceptibility of YBa2Cu3O7-{\delta} thin films. The proposed theoretical mechanism on the oxygen and its vacancies diffusion in YBa2Cu3O7-{\delta} superconducting thin films near to the centers of Abricosov magnetic vortices cores at the action of the superconducting electron pair potential gradient explains the observed physical properties. 
Viktor O. Ledenyov, Dimitri O. Ledenyov and Oleg P. Ledenyov
cond-mat.supr-con