在薄膜II型超导体中,自场临界电流密度的极限
Amit Goyal1, Rohit Kumar1, Armando Galluzzi2
1Laboratory for Heteroepitaxial Growth of Functional Materials & Devices, Department of Chemical & Biological Engineering, State University of New York (SUNY) at Buffalo, Buffalo, NY 14260, USA.
Materials (Basel, Switzerland)
|February 27, 2026
概括
对于II型超导体中自场临界电流密度的普遍的Silsbee-like极限并不普遍有效. 实验数据和人工固定中心显示,更高的电流密度是可以实现的,这表明需要对理解进行修订.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
- 超导电性 超导电性 超导电性
背景情况:
- 自场的临界电流密度 (Jc(s.f.)) 在II型超导体中被认为基本上受到Silsbee-like标准 (Jc(s.f.) 的限制. = Hc1/λ) 的值.
- 几十年来,这一理论极限一直指导着超导材料的研究和开发.
研究的目的:
- 质疑Silsbee-like标准对II型超导体中自场临界电流密度的普遍有效性.
- 调查影响Jc(s.f.) 的因素. 超出了这个既定限制.
- 探索增强Jc(s.f.) 的潜力 用于实际应用.
主要方法:
- 实验测量Jc (sf) 的情况. 在YBa2Cu3O7-δ和REBa2Cu3O7-δ薄膜,以及Nb薄膜中.
- 实验中的Jc(s.f.) 的比较 用基于Silsbee-like标准进行计算的值.
- 研究将人工结中心 (APC) 纳入 Jc(s.f. 的影响. ) 的情况.
主要成果:
- 实验性的 Jc ((s.f.) 的使用. 发现各种薄膜 (YBa2Cu3O7-δ,REBa2Cu3O7-δ,Nb) 中的值大大超过了类似于Silsbee的标准预测.
- 整合了 APC 显著改善了 Jc(s.f. ),证明这个参数不是一个固定的通用上限.
- 这些发现表明,对II型超导体带电极限的公认理解需要修订.
结论:
- 类似于西尔斯比的标准不是对II型超导体的自场临界电流密度的普遍有效极限.
- 人工钉钉中心提供了一条可行的途径,可以显著增强Jc(s.f.) 超出了理论限制.
- 在基于REBCO的涂层导体中优化APC对于商业核聚变等大规模应用具有相当大的潜力.
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