论文标题
shiba状态在具有奇异性密度的系统中
Shiba states in systems with density of states singularities
论文作者
论文摘要
放置在超导体中的磁杂质会导致Yu-Shiba-Rusinov结合状态的出现。杂质和底物之间的耦合取决于费米水平的状态密度（DOS），并且可以通过DOS奇异性来调节。在本文中，我们使用所选晶格模型的真实空间Bogoliubov-de Gennes方程研究DOS奇异性的作用。为了揭示这些奇异性的作用（Dirac Point，Van Hove Singularity或Flat Band），我们研究了Honeycomb，Kagome和Lieb Lattices。我们表明，志着人状态的特性在很大程度上取决于晶格的类型。然而，某些行为是通用的，例如临界磁耦合在费米水平上DOS的依赖性。然而，志着国家在Lieb晶格中意识到的表现出了非凡的特性，可以通过一些不需要的sublattices来解释。根据所选sublattice磁杂质的位置，当平坦频段位于费米级时，可以减少或增强临界磁耦合$ j_ \ text {c} $的值。在这种情况下，我们还提出了Lieb晶格中不同sublattices的局部DOS和相干长度的差异。
Magnetic impurities placed in the superconductor can lead to emergence of the Yu-Shiba-Rusinov bound states. Coupling between the impurity and the substrate depends on density of states (DOS) at the Fermi level and can be tuned by DOS singularities. In this paper, we study the role of DOS singularities using the real space Bogoliubov-de Gennes equations for chosen lattice models. To uncover the role of these singularities (Dirac point, van Hove singularity, or the flat band), we study honeycomb, kagome, and Lieb lattices. We show that the properties of the Shiba state strongly depends on the type of lattice. Nevertheless some behaviors are generic, e.g. dependence of the critical magnetic coupling on the DOS at the Fermi level. However, the Shiba states realized in the Lieb lattice exhibit extraordinary properties, which can be explained by the presence of a few nonequivalent sublattices. Depending on the location of the magnetic impurity in the chosen sublattice, the value of critical magnetic coupling $J_\text{c}$ can be reduced or enhanced when the flat band is located at the Fermi level. In this context, we also present differences in the local DOS and coherence lengths for different sublattices in the Lieb lattice.
