High quality YBCO superconductive thin films fabricated by laser molecularbeam epitaxy

High quality YBa2Cu3O6+x (YBCO) superconductive thin films have been fabric ated on the SrTiO3(100) substrate using laser molecular beam epitaxy (laser -MBE). The active oxygen source was used, which made the necessary ambient oxygen pressure be 2-3 orders lower than that in pulsed laser deposition (P LD). T-c0 is 85-87 K, and J(c) similar to 1.0 x 10(6) A/cm(2). Atomic force microscopy (AFM) measurements show that no obvious particulates can be obs erved and the root mean square roughness is 7.8 nm. High stability DC super conducting quantum interference devices ( DC-SQUID) was fabricated using th is YBCO thin film.