Investigation of Optically Modified YBa2Cu3O7–x Films by Means of X-ray Microanalysis Technique

Abstract

This work reports on investigation of remnant oxygen content in optically-modified regions of 0.3-μm-thick YBa 2 Cu 3 O 7-x films, patterned by a laser-writing technique in an inert ambient gas atmosphere at room temperature. A laser-treated region of weak superconductivity with dimensions depending on the size of a laser spot, laser power, and initial content of oxygen is characterized by a lower oxygen content, weaker critical magnetic field, and suppressed both the superconducting critical temperature and the critical current density, as compared to the laser untreated regions. Optically induced (cw-laser, 532-nm-wavelength) heating strongly affects a non-uniform distribution of remnant oxygen content in the film, depending both on the optical power and beam's scanning velocity. A level of oxygen depletion and the size of the oxygen-deficient region have been directly estimated from scanning-electron-microscope spectra with the X-ray microanalysis technique. The results of our measurements were compared with results extracted from electric measurements, assuming a correlation between the remnant oxygen content and the electric transport properties of oxygen-deficient YBa 2 Cu 3 O 7-x films. Keywords: YBa 2 Cu 3 O 7-x superconducting thin films, oxygen deficient superconductor, remnant oxygen content, light interaction with superconducting material, laser-writing technique.