Spin-polarized edge currents and Majorana fermions in one- and two-dimensional topological superconductors

被引：43

作者：

Bjornson, Kristofer ^{[1
]}

Pershoguba, Sergey S. ^{[2
,3
]}

Balatsky, Alexander V. ^{[2
,3
,4
]}

Black-Schaffer, Annica M. ^{[1
]}

机构：

[1] Uppsala Univ, Dept Phys & Astron, S-75120 Uppsala, Sweden

[2] KTH Royal Inst Technol, Ctr Quantum Mat, Nordita, S-10691 Stockholm, Sweden

[3] Stockholm Univ, S-10691 Stockholm, Sweden

[4] Los Alamos Natl Lab, Inst Mat Sci, Los Alamos, NM 87545 USA

来源：

PHYSICAL REVIEW B | 2015年 / 92卷 / 21期

基金：

欧洲研究理事会; 瑞典研究理事会;

关键词：

SINGLE DIRAC CONE; INSULATOR; NANOWIRE; SIGNATURE;

D O I：

10.1103/PhysRevB.92.214501

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

We investigate the persistent currents, spin-polarized local density of states, and spectral functions of topological superconductors constructed by placing ferromagnetic impurities on top of an s-wave superconductor with Rashba spin-orbit interaction. We solve self-consistently for the superconducting order parameter and investigate both two-dimensional blocks and one-dimensional wires of ferromagnetic impurities, with the magnetic moments pointing both perpendicular and parallel to the surface. We find that the topologically protected edge states of ferromagnetic blocks give rise to spin-polarized edge currents, but that the total persistent current flows in opposite direction to what is expected from the dispersion relation of the edge states. We also show that the Majorana fermions at the end points of one-dimensional wires are spin polarized, which can be directly related to the spin polarization of the edge currents of two-dimensional blocks. Connections are also made to the physics of the Yu-Shiba-Rusinov states for zero-dimensional impurities.

引用

页数：17

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