Gutiérrez J, Llordés A, Gázquez J, Gibert M, Romà N, Ricart S, Pomar A, Sandiumenge F, Mestres N, Puig T, Obradors X
Institut de Ciència de Materials de Barcelona, C.S.I.C., Campus U.A. Barcelona, 08193 Bellaterra, Catalonia, Spain.
Nat Mater. 2007 May;6(5):367-73. doi: 10.1038/nmat1893. Epub 2007 Apr 22.
Power applications of superconductors will be tremendously boosted if an effective method for magnetic flux immobilization is discovered. Here, we report the most efficient vortex-pinning mechanism reported so far which, in addition, is based on a low-cost chemical solution deposition technique. A dense array of defects in the superconducting matrix is induced in YBa(2)Cu(3)O(7-x)-BaZrO(3) nanocomposites where BaZrO(3) nanodots are randomly oriented. Non-coherent interfaces are the driving force for generating a new type of nanostructured superconductor. Angle-dependent critical-current measurements demonstrate that a strong and isotropic flux-pinning mechanism is extremely effective at high temperatures and high magnetic fields leading to high-temperature superconductors with record values of pinning force. The maximum vortex-pinning force achieved at 65 K, 78 GN m(-3), is 500% higher than that of the best low-temperature NbTi superconductors at 4.2 K and so a great wealth of high-field applications will be possible at high temperatures.
如果能发现一种有效的磁通量固定方法，超导电力应用将得到极大推动。在此，我们报道了迄今为止最有效的涡旋钉扎机制，此外，该机制基于一种低成本的化学溶液沉积技术。在YBa₂Cu₃O₇₋ₓ - BaZrO₃纳米复合材料中诱导出超导基质中的密集缺陷阵列，其中BaZrO₃纳米点随机取向。非相干界面是生成新型纳米结构超导体的驱动力。角度相关的临界电流测量表明，一种强且各向同性的磁通钉扎机制在高温和高磁场下极其有效，从而导致具有创纪录钉扎力值的高温超导体。在65 K时实现的最大涡旋钉扎力为78 GN m⁻³，比最佳低温NbTi超导体在4.2 K时的钉扎力高500%，因此在高温下将有可能实现大量的高场应用。
