论文标题
基于第一原理
Proximity effect in a superconductor-topological insulator heterostructure based on first principles
论文作者
论文摘要
有人认为超导体 - 容器绝缘子（SC-TI）异质结构是实现和控制Majora零模型的可能平台。尽管实验性签名表明其存在，但对观察到的特征的单局解释需要包括现实的电子结构在内的理论。为了实现这一目标，我们在完全相对论的korringa-kohn-rostoker方法中解决了超薄bi $ _2 $ _2 $ se $ _3 $胶片的Kohn-Sham-Dirac-bogoliubov-de Gennes方程式，并在完全相对的Korringa-kohn rostoker中进行了胶片，并调查了化学势和膜厚度的Quasiparticle spectra。我们发现强烈依赖性近端诱导的间隙特征，其中差距大小高度取决于Ti状态的特征。仅当化学势接近狄拉克点能量时，ti dirac状态与诱导的差距有关。否则，在给定的化学电位上，最大的诱导间隙来自最高能量的量子孔状态，而最小的间隙来自Ti拓扑表面状态，其间隙大小取决于TI配对的电位。
Superconductor-topological insulator (SC-TI) heterostructures were proposed to be a possible platform to realize and control Majorana zero-modes. Despite experimental signatures indicating their existence, univocal interpretation of the observed features demands theories including realistic electronic structures. To achieve this, we solve the Kohn-Sham-Dirac-Bogoliubov-de Gennes equations for ultrathin Bi$_2$Se$_3$ films on superconductor PdTe, within the fully relativistic Korringa-Kohn-Rostoker method, and investigate quasiparticle spectra as a function of chemical potential and film thickness. We find a strongly momentum-dependent proximity-induced gap feature where the gap sizes highly depend on characteristics of the TI states. The interface TI Dirac state is relevant to the induced gap only when the chemical potential is close to the Dirac-point energy. Otherwise, at a given chemical potential, the largest induced gap arises from the highest-energy quantum-well states, whereas the smallest gap arises from the TI topological surface state with its gap size depending on the TI pairing potential.
