论文标题
探索Bogoliubov-De Gennes无序超导体的涡流相图
Exploring the vortex phase diagram of Bogoliubov-de Gennes disordered superconductors
论文作者
论文摘要
我们研究了Bogoliubov-De Gennes（BDG）在零温度下的二维无序超导体中的涡流和疾病的相互作用，该尺寸的晶格最高为$ 100 \ times100 $，在其中Peierls的取代引入了磁性磁通量。比以前的方法（$ \ \ leq 36 \ times 36 $）更大的大小使我们能够识别出丰富的相图作为磁通量和无序强度的函数。对于足够弱的疾病，磁通量不是太强的磁通量，我们观察到一个略微扭曲的Abrikosov三角形涡流晶格。磁通量的增加导致意外的矩形涡流晶格。尽管强烈的涡流排斥力持续存在，但疾病的进一步增加或通量逐渐破坏了晶格对称性。更强的疾病会导致具有不均匀核心的变形单个涡旋。随着涡度数量的增加，涡旋重叠变得更加频繁。最后，我们表明全局相干性是所有这些阶段的特征，并且疾病相对于清洁极限，大大增强了临界磁通量，并且最大值在绝缘过渡的金属侧。
We study the interplay of vortices and disorder in a two-dimensional disordered superconductor at zero temperature described by the Bogoliubov-de Gennes (BdG) self-consistent formalism for lattices of sizes up to $100\times100$ where the magnetic flux is introduced by the Peierls's substitution. The substantial larger size than in previous approaches ($\leq 36\times 36$) has allowed us to identify a rich phase diagram as a function of the magnetic flux and the disorder strength. For sufficiently weak disorder, and not too strong magnetic flux, we observe a slightly distorted Abrikosov triangular vortex lattice. An increase in the magnetic flux leads to an unexpected rectangular vortex lattice. A further increase in disorder, or flux gradually destroy the lattice symmetry though strong vortex repulsion persists. An even stronger disorder leads to deformed single vortices with an inhomogeneous core. As number of vortices increases, vortices overlap becomes more frequent. Finally, we show that global phase coherence is a feature of all these phases and that disorder enhances substantially the critical magnetic flux with respect to the clean limit with a maximum on the metallic side of the insulating transition.
