Positron study of oxygen diffusion and electronic structure for superconductor YBa₂Cu₃O_6+x

Experimental results of positron lifetime data of superconductor YBa₂Cu₃O_6+x under different oxygen diffusion conditions have been presented. It is found that a difference exists in local electronic structure of Cu-O chains with all the other same factors, except different sintering temperatures. Through the connection between oxygen diffusion and electronic structure, it is proved that the best oxygen diffusion condition exists in the process of making the superconductor YBa₂Cu₃O_6+x.