Inducing superconducting correlation in quantum Hall edge states
Inducing superconducting correlation in quantum Hall edge states
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DOI：
10.1038/nphys4084
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发表时间：
2017-07-01
期刊：
影响因子：
19.6
通讯作者：
Kim, Philip
中科院分区：
文献类型：
--
作者：
Lee, Gil-Ho;Huang, Ko-Fan;Kim, Philip
量子霍尔（QH）效应在二维系统的边界处支持一组手征边缘态。超导体（SC）接触这些状态可以提供在无耗散的边缘态的准粒子的关联。在这里，我们制造了高度透明和纳米级的SC结到石墨烯。我们证明了QH边缘态可以通过比超导相干长度更窄的SC电极通过超导关联耦合。我们观察到，边缘状态的化学势表现出跨SC电极的符号反转。这提供了进入的电子沿着手性边缘态沿着到出射的空穴的转换的直接证据，称为交叉Andreev转换（CAC）。我们表明，CAC可以成功地描述温度，偏压和SC电极宽度的依赖性。这种混合SC/QH系统可以提供一种新的途径来创建孤立的非阿贝尔任意零模，与手征边缘态共振。
The quantum Hall (QH) effect supports a set of chiral edge states at the boundary of a two-dimensional system. A superconductor (SC) contacting these states can provide correlations of the quasiparticles in the dissipationless edge states. Here we fabricated highly transparent and nanometre-scale SC junctions to graphene. We demonstrate that the QH edge states can couple via superconducting correlations through the SC electrode narrower than the superconducting coherence length. We observe that the chemical potential of the edge state exhibits a sign reversal across the SC electrode. This provides direct evidence of conversion of the incoming electron to the outgoing hole along the chiral edge state, termed crossed Andreev conversion (CAC). We show that CAC can successfully describe the temperature, bias and SC electrode width dependences. This hybrid SC/QH system could provide a novel route to create isolated non-Abelian anyonic zero modes, in resonance with the chiral edge states.