论文标题
在空间上分散Yu-Shiba-Rusinov在非常规的超导体$ \ mathrm {fete} _ {0.55} \ Mathrm {se} _ {0.45} $
Spatially dispersing Yu-Shiba-Rusinov states in the unconventional superconductor $\mathrm{FeTe}_{0.55}\mathrm{Se}_{0.45}$
论文作者
论文摘要
By using scanning tunneling microscopy (STM) we find and characterize dispersive, energy-symmetric in-gap states in the iron-based superconductor $\mathrm{FeTe}_{0.55}\mathrm{Se}_{0.45}$, a material that exhibits signatures of topological superconductivity, and Majorana bound states at vortex cores or at impurity位置。我们使用超导STM尖端来增强能量分辨率，这使我们能够证明杂质状态可以通过不同的尖端样本距离调节费米水平。我们发现杂质状态是Yu-Shiba-Rusinov（YSR）类型的类型，并认为能量转移是由$ \ Mathrm {Fete} _ {0.55} \ Mathrm {0.55} \ Mathrm {Se} _ {0.45} $的低超级流体密度引起的，该_ {0.45} $允许略微渗透式的电气场。我们对单障碍安德森模型中新引入的小费门票方案进行建模，并与实验数据找到良好的一致性。
By using scanning tunneling microscopy (STM) we find and characterize dispersive, energy-symmetric in-gap states in the iron-based superconductor $\mathrm{FeTe}_{0.55}\mathrm{Se}_{0.45}$, a material that exhibits signatures of topological superconductivity, and Majorana bound states at vortex cores or at impurity locations. We use a superconducting STM tip for enhanced energy resolution, which enables us to show that impurity states can be tuned through the Fermi level with varying tip-sample distance. We find that the impurity state is of the Yu-Shiba-Rusinov (YSR) type, and argue that the energy shift is caused by the low superfluid density in $\mathrm{FeTe}_{0.55}\mathrm{Se}_{0.45}$, which allows the electric field of the tip to slightly penetrate the sample. We model the newly introduced tip-gating scenario within the single-impurity Anderson model and find good agreement to the experimental data.
