Prof.  Yao  Xin
Shanghai Jiao Tong University,  China

Title: Artificial microstructures in oriented films of LPE-processed Y123 for fundamental researches and device application

Abstract:

Different microstructures of high temperature superconductor (HTS) suit for different applications. For instance, c-axis orientated YBa2Cu3O7-δ (YEBCO) films are appropriate for current transport approach, while a-axis oriented films are suitable for device applications. Besides, grain boundaries (GBs) with a special structure are of great potential to improve superconducting performance. Thus, it is of significant importance to realize artificial control of film microstructures. Among numerous preparation methods, the liquid phase epitaxy (LPE) technique has many advantages with respect to the film growth, such as high crystalline quality, low cost, high growth rate and so on. Over the years, we have been making efforts in the field of the artificial control of film microstructures for LPE-processed YBCO by tuning solute supersaturation state. The main scientific significance of this presentation is to interpret the nature of oriented film growth, to introduce several novel approaches for effective control the supersaturation state in solution with a wide range from low, intermediate to high levels, to reliably prepare a variety of oriented microstructures for potential applications. Through the work presented here, we hope to provide specific guidance for orientation control of REBa2Cu3O7-δ (RE = rare earth element) films, and the preparation of some distinctive GBs.

Biography:

Prof. X. Yao, from Shanghai Jiao Tong Univ., got his Bachelor and Master degrees in Dept. Mater. Sci. and Eng., of Shanghai Jiao Tong Univ., and got his Ph.D. at Univ. of Liverpool, in. 1993. He was a research scientist at ISTEC（International Superconductivity Technology Center） in Japan (1993-2001). During work at ISTEC, he has grown the world record, large-sized REBCO single crystals. In his new lab at Shanghai Jiao Tong Univ (from 2002), he has extended the growth of REBCO crystals to the bulks and LPE films, focusing his interests on the phase formation and the growth mode in various RE-Ba-Cu-O systems.