Critical current density of high‐quality Bi2Sr2Ca2Cu3Ox thin films prepared by metalorganic chemical‐vapor deposition

Critical current densities Jc were measured in as‐deposited, c‐axis‐oriented Bi2Sr2Ca2Cu3Ox thin films with Tc values as high as 97 K, which were prepared by metalorganic chemical‐vapor deposition. These films showed high Jc (≳109 A/m2) at 77.3 K in high magnetic fields (≥1 T, H∥a‐b plane). The best values are 3.3×109 A/m2 at 1 T and 9.1×108 A/m2 at 8 T, which are the highest Jc for Bi‐oxide thin films among those reported so far. There were no signs of weak links in the Jc(H) behavior, and the surface morphology examined by scanning electron microscopy showed no apparent grain boundaries. The values of Jc decreased sharply when the applied field deviated from the a‐b plane, and went to zero at the angles where the field component in the c direction is nearly equal to the irreversibility field Hc2* parallel to the c axis. The angular dependence of Jc of these films is most reasonably explained by the theory of intrinsic pinning.

[1]  Ando,et al.  Mechanism of the Lorentz-force-independent dissipation in Bi2Sr2CaCu2Oy. , 1991, Physical review letters.

[2]  J. Juang,et al.  The magnetic and transport properties of high‐critical‐current Tl2Ba2Ca2Cu3Ox superconducting thin films , 1991 .

[3]  Clem,et al.  Lower critical field of a Josephson-coupled layer model of high-Tc superconductors. , 1991, Physical Review B (Condensed Matter).

[4]  H. Maeda,et al.  Anisotropy of critical current density in textured Bi2Sr2Ca1Cu2Ox tapes , 1991 .

[5]  Y. Iye,et al.  Dissipation in extremely anisotropic layered superconductor in parallel magnetic field , 1991 .

[6]  S. Liou,et al.  Effects of Magnetic Field and Temperature on the Critical Current Hysteresis in Tl-Ca-Ba-Cu-O Thin Films , 1990 .

[7]  Yukikazu Iwasa,et al.  Critical currents of superconducting BiPbSrCaCuO tapes in the magnetic flux density range 0–19.75 T at 4.2, 15, and 20 K , 1990 .

[8]  J. Ekin,et al.  Transport critical current of aligned polycrystalline Y1Ba2Cu3O7−δ and evidence for a nonweak‐linked component of intergranular current conduction , 1990 .

[9]  C. Beduz,et al.  Irreversibility and hysteretic aspects of granular YBCO , 1990 .

[10]  Schultz,et al.  Anisotropy of the critical current density in epitaxial YBa2Cu3Ox films. , 1990, Physical review letters.

[11]  M. Tachiki,et al.  Anisotropy of critical current in layered oxide superconductors , 1989 .

[12]  T. Hirai,et al.  Critical Current Criterion in High-Tc Superconducting Films , 1989 .

[13]  D. Dew-Hughes,et al.  Contact problems in Jc measurements on high Tc superconductors , 1989 .

[14]  K. Watanabe,et al.  Resistive transition in YBa2Cu3Oz and Bi2(Sr,Ca)3Cu2Oz CVD films under high magnetic field , 1989 .

[15]  M. Tachiki,et al.  Strong vortex pinning intrinsic in high-Tc oxide superconductors , 1989 .

[16]  K. Yamafuji,et al.  Anisotropy and hysteresis of transport critical currents in high temperature Ln-Y-Ba-Cu-O superconductors , 1989 .

[17]  K. Watanabe,et al.  Critical Currents at 77.3 K under Magnetic Fields up to 27 T for an Y-Ba-Cu-O Film Prepared by Chemical Vapor Deposition , 1989 .

[18]  Tinkham.  Resistive transition of high-temperature superconductors. , 1988, Physical review letters.

[19]  D. Larbalestier,et al.  Weak links and the poor transport critical currents of the 123 compounds , 1988 .

[20]  M. Gijs,et al.  Critical current as a function of temperature in thin YBa2Cu3O7−δ films , 1988 .

[21]  Malozemoff,et al.  Giant flux creep and irreversibility in an Y-Ba-Cu-O crystal: An alternative to the superconducting-glass model. , 1988, Physical review letters.

[22]  M. Fukutomi,et al.  A New High-Tc Oxide Superconductor without a Rare Earth Element , 1988 .

[23]  J. Kwo,et al.  Evidence for weak link and anisotropy limitations on the transport critical current in bulk polycrystalline Y1Ba2Cu3Ox , 1987 .

[24]  M. Beasley,et al.  Critical current densities and transport in superconducting YBa2Cu3O7−δ films made by electron beam coevaporation , 1987 .

[25]  Toshiaki Murakami,et al.  Largely Anisotropic Superconducting Critical Current in Epitaxially Grown Ba2YCu3O7-y Thin Film , 1987 .

[26]  McGuire,et al.  Critical-current measurements in epitaxial films of YBa2Cu , 1987, Physical review letters.

[27]  D. Larbalestier,et al.  Critical current distributions in superconducting composites , 1986 .

[28]  Philip W. Anderson,et al.  Theory of Flux Creep in Hard Superconductors , 1962 .

[29]  H. Hayakawa,et al.  Advances in Superconductivity IV , 1992 .

[30]  K. Endo,et al.  High-quality superconducting thin films of Bi2Sr2Ca2Cu3Ox grown in situ by metalorganic CVD , 1992, Nature.

[31]  P. Monceau,et al.  Critical current anisotropy of BiSrCaCuO thin films under magnetic fields , 1991 .

[32]  H. Hayakawa,et al.  Advances in Superconductivity III , 1991 .

[33]  T. Ishiguro,et al.  Advances in Superconductivity II , 1990 .

[34]  Koichi Kitazawa,et al.  Advances in superconductivity , 1989 .

[35]  K. Müller,et al.  Flux trapping and superconductive glass state in La2CuO4-y:Ba. , 1987, Physical review letters.

[36]  Michael Tinkham,et al.  Introduction to Superconductivity , 1975 .

[37]  P. Anderson,et al.  HARD SUPERCONDUCTIVITY: THEORY OF THE MOTION OF ABRIKOSOV FLUX LINES , 1964 .