Dahlem Center for Complex Quantum Systems and Fachbereich Physik, Freie Universität Berlin, 14195 Berlin, Germany.
Department of Physics, Yale University, New Haven, Connecticut 06520, USA.
Phys Rev Lett. 2015 Mar 13;114(10):106801. doi: 10.1103/PhysRevLett.114.106801. Epub 2015 Mar 9.
A recent experiment [Nadj-Perge et al, Science 346, 602 (2014)] gives possible evidence for Majorana bound states in chains of magnetic adatoms placed on a superconductor. While many features of the observed end states are naturally interpreted in terms of Majorana states, their strong localization remained puzzling. We consider a linear chain of Anderson impurities on a superconductor as a minimal model and treat it largely analytically within mean-field theory. We explore the phase diagram, the subgap excitation spectrum, and the Majorana wave functions. Owing to a strong velocity renormalization, the latter are localized on a scale which is parametrically small compared to the coherence length of the host superconductor.
最近的一项实验[Nadj-Perge 等人，《科学》346, 602（2014）]为放置在超导体上的磁性 adatoms 链中的马约拉纳束缚态提供了可能的证据。虽然观察到的末端状态的许多特征自然可以用马约拉纳态来解释，但它们的强局域性仍然令人困惑。我们将超导体内的安德森杂质线性链作为一个最小模型，并在平均场理论中进行了大量的分析。我们探索了相图、能隙激发谱和马约拉纳波函数。由于强速度重整化，后者在与宿主超导体的相干长度相比参数小得多的尺度上局域化。
