论文标题
超导硼掺杂钻石薄膜中的Wohlleben效应和新兴的PI连接
Wohlleben Effect and Emergent Pi junctions in superconducting Boron doped Diamond thin films
论文作者
论文摘要
Diamond是一款出色的绝缘体。然而，已知硼（B）掺杂会诱导超导性。我们在超导B掺杂钻石（BDD）薄膜中提出了两个有趣的效果：i）wohleben效应（Pramagnetic Meissner效应，PME）和II）像易感异常一样的低场旋转玻璃。我们在掺杂（1.4、2.6和3.6）x 1021 cm-3的温度范围2-10 K. pme的掺杂（1.4、2.6和3.6）x 1021 cm-3上进行了电气和磁性测量，在不均匀的超导体中，低场异常可能会因通量捕获，磁通量压缩而出现，或者是无效的原因，或者出现了无效的原因。 PME和自旋玻璃型异常的关节出现指向PI连接的可能出现。 BDD是无序的S波超导体；当存在于弱超导区域时，可以通过自旋半矩的自旋翻转散射来产生PI连接（Bulaevski等，1978）。沮丧的0和PI连接网络将导致自发平衡超超电流的分布（Kusmartse等，1992）。安德森局部嵌入金属流体中的旋转半旋子（Bhatt等人的两个流体模型）可以通过自旋翻转散射产生PI结。我们的发现与PI连接的存在一致，并引用了他们（Bhattacharyya等）对BDD中某些抗药性异常的观察。
Diamond is an excellent band insulator. However, boron (B) doping is known to induce superconductivity. We present two interesting effects in superconducting B doped diamond (BDD) thin films: i) Wohlleben effect (paramagnetic Meissner effect, PME) and ii) a low field spin glass like susceptibility anomaly. We have performed electrical and magnetic measurements (under pressure in one sample) at dopings (1.4 , 2.6 and 3.6) X 1021 cm-3, in a temperature range 2 - 10 K. PME, a low field anomaly in inhomogeneous superconductors could arise from flux trapping, flux compression, or for non-trivial reason such as emergent Josephson Pi junctions. Joint occurrence of PME and spin glass type anomalies points to possible emergence of Pi junctions. BDD is a disordered s-wave superconductor; and Pi junctions could be produced by spin flip scattering of spin half moments when present at weak superconducting regions (Bulaevski et al. 1978). A frustrated network of 0 and Pi junctions will result (Kusmartsev et al. 1992) in a distribution of spontaneous equilibrium supercurrents, a phase glass state. Anderson localized spin half spinons embedded in a metallic fluid (two fluid model of Bhatt et al.) could create Pi junction by spin flip scattering. Our findings are consistent with presence of Pi junctions, invoked to explain their (Bhattacharyya et al.) observation of certain resistance anomaly in BDD.
