Microwave absorption in YBa2Cu3O x granular thin films at the dc magnetic fields

Localization of microwave absorption in YBa₂Cu₃O _x superconducting thin films in the presence of very low dc magnetic field was studied. The granular YBa₂Cu₃O _x thin films of submicrometer thickness had random orientation of grains, were inserted into a microwave cavity for maximum rf magnetic field. The microwave absorption in low dc magnetic field at temperatures just below the critical temperature shows properties which may be ascribed to superconducting grains. At lower temperatures the hysteretic effects and flux-trapping occur in the intergrain regions of the film.