We fabricated a compact (13 12 12.5 mm³) trapped-field magnet by stacking 200 pieces of EuBa₂Cu₃O₇ coated conductors (CCs) with BaHfO₃ nanorods as artificial pinning centers. It was magnetized by field-cooling method using a 18 T superconducting magnet, and the maximum field of 14.8 T was trapped at 10 K at a field-ramp rate of 0.1 T min⁻¹. At higher temperatures, although the trapped field was decreased, we could trap the field with much faster ramp rate. In order to understand these results, we also performed calculations of the trapped field based on characteristics of the CC. The calculated trapped field value was larger than the experimental value at 10 K. This discrepancy can be understood by considering the reduction of the effective size of the stacked CCs due to the existence of extended regions of irregular flux penetration called ‘flux jets’.

我们通过堆叠 200 片 EuBa ₂ Cu ₃ O ₇涂层导体 (CC)，以 BaHfO ₃纳米棒作为人工钉扎中心，制造了一种紧凑的 (13 12 12.5 mm ³ ) 陷场磁体。它使用 18 T 超导磁体通过场冷却方法磁化，14.8 T 的最大场在 10 K 时以 0.1 T min ^-1的场斜坡率被俘获。在更高的温度下，虽然俘获场减少了，但我们可以以更快的斜坡速率俘获场。为了理解这些结果，我们还进行了基于捕获场的计算CC的特点。计算的俘获场值大于 10 K 时的实验值。这种差异可以通过考虑由于存在称为“通量射流”的不规则通量穿透扩展区域而导致的堆叠 CC 的有效尺寸减小来理解。