Understanding high critical currents in YBa2Cu3O7 thin films and coated conductors

L. CIVALE; B. MAIOROV; A. SERQUIS; J. O. WILLIS; Y. J. COULTER; H. WANG; Q. X. JIA; P. N. ARENDT; M. JAIME; J. L. MACMANUS-DRISCOLL; M. P. MALEY; S. R. FOLTYN

JOURNAL OF LOW TEMPERATURE PHYSICS

Springer Netherlands

Año: 2004 vol. 135 p. 87 - 98

0022-2291

The main challenges for the success of high temperature superconductingwires, the YBa2Cu3O7 (YBCO) coated conductors (CC), are to avoid thethe weak-link problem through the production of biaxially textured films, andto increase the critical current density (Jc) through the introduction of largedensities of appropriate defects. To that end, it is essential to understandthe pinning mechanisms and their correlation with the microstructure of theCC. We first present a brief overview of the main methods currently usedto produce YBCO CC, and we describe the architecture of the YBCO onIBAD fabricated at Los Alamos, summarizing the recent improvements oftheir structural and superconducting properties. Then, we analyze some aspectsof the Jc dependence on temperature and magnetic field (orientationand intensity) for the best CC available, and we compare and contrast theresults with those of YBCO thin films on single crystal substrates, in orderto determine if the defects controlling the pinning mechanisms are the samein both cases. Our results indicate that over large field and angular rangesJc on CC is higher than Jc in thin films on SCS.