arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1807.04201cond-mat.mes-hallcond-mat.str-elcond-mat.supr-con
收藏

朗道能级上的拓扑超导性

Topological superconductivity in Landau levels

Gun Sang Jeon, J. K. Jain, C. -X. Liu

摘要:

对拓扑超导性的强烈探索是受到它拥有马约拉纳准粒子的前景的启发。在这项工作中,我们探讨了最佳的设计生产拓扑超导相结合的量子霍尔态与普通超导体。为此,我们考虑了一个微观模型的拓扑平凡的二维p波超导体暴露于磁场中,并发现超导性和朗道能级物理的相互作用产生了丰富的相图的状态作为一个功能的$μ/t$和$Δ/t$,其中$μ$,$t$和$Δ$是化学势,跳跃强度,和超导能隙的振幅。除了量子霍尔态和拓扑平凡的p波超导体之外,相图还包含拓扑超导性的区域。最重要的是,我们发现,应用程序的非均匀的,周期性的磁场产生的正方形或六角形晶格的$h/e$磁通大大促进区域的拓扑超导性的限制$Δ/t\rightarrow 0$。相比之下,均匀磁场、$h/2e$类磁通量的六方Abrikosov晶格或一维条纹晶格仅对足够大的$Δ/t$产生拓扑超导性。

英文摘要:

The intense search for topological superconductivity is inspired by the prospect that it hosts Majorana quasiparticles. We explore in this work the optimal design for producing topological superconductivity by combining a quantum Hall state with an ordinary superconductor. To this end, we consider a microscopic model for a topologically trivial two-dimensional p-wave superconductor exposed to a magnetic field, and find that the interplay of superconductivity and Landau level physics yields a rich phase diagram of states as a function of $μ/t$ and $Δ/t$, where $μ$, $t$ and $Δ$ are the chemical potential, hopping strength, and the amplitude of the superconducting gap. In addition to quantum Hall states and topologically trivial p-wave superconductor, the phase diagram also accommodates regions of topological superconductivity. Most importantly, we find that application of a non-uniform, periodic magnetic field produced by a square or a hexagonal lattice of $h/e$ fluxoids greatly facilitates regions of topological superconductivity in the limit of $Δ/t\rightarrow 0$. In contrast, a uniform magnetic field, a hexagonal Abrikosov lattice of $h/2e$ fluxoids, or a one dimensional lattice of stripes produces topological superconductivity only for sufficiently large $Δ/t$.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑