单晶铅膜中的反常量子Griffiths奇异性
Anomalous quantum Griffiths singularity in ultrathin crystalline lead films
摘要：
研究了磁场诱导的铅超导薄膜的超导-金属转变。通过超低温输运测量，在接近零温量子临界点时，观察到了发散临界指数作为量子Griffiths奇点（QGS）的指示。不同的是，SMT的相边界在低温区表现出一种反常的行为，即起始临界场随温度的降低而降低，这使我们的观察与早期报道的各种二维超导体中的QGS不同。我们证明，这种观察到的异常相边界有其起源从超导涨落在Pb-Pb薄膜。我们的发现揭示了二维超导系统中具有反常相界的SMT的QGS的一个新的方面。
英文摘要：
We study the magnetic field induced superconductor-metal transition (SMT) in ultrathin crystalline Pb films. By performing ultralow temperature transport measurement, the divergent critical exponent as an indication of quantum Griffiths singularity (QGS) is observed when approaching zero temperature quantum critical point. Distinctively, the phase boundary of SMT exhibits an anomalous behavior in low temperature regime that the onset critical field decreases with decreasing temperatures, which distinguishes our observation from earlier reports of QGS in various two-dimensional superconductors. We demonstrate that this observed anomalous phase boundary has its origin from the superconducting fluctuations in ultrathin Pb films. Our findings reveal a novel aspect of the QGS of SMT in two-dimentional superconducting systems with anomalous phase boundary.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
