Photoexcitation and oxygen ordering in YBa2Cu3Ox films

Abstract

We report on the photoinduced enhancement of the critical temperature δTc and the in-plane conductivity δσab measured in a c-axis-oriented YBa2Cu3Ox film as a function of oxygen concentration (6.4≤x≤7). Both δTc and δσab decrease with the oxygen content, display a plateaulike behavior for 6.6≤x≤6.75, and become zero at x=7. This dependence of δTc on x is similar to that observed for the Tc enhancement due to ordering effects in oxygen-deficient YBa2Cu3Ox single crystals. We propose that the persistent photoinduced changes in YBa2Cu3Ox films are due to photoassisted oxygen ordering.