Crossed Andreev effects in two-dimensional quantum Hall systems
Crossed Andreev effects in two-dimensional quantum Hall systems
复制标题
DOI：
10.1103/physrevb.94.064516
复制
发表时间：
2016-08
影响因子：
3.7
通讯作者：
Z. Hou;Yanxia Xing;Ai-Min Guo;Qing-feng Sun
中科院分区：
文献类型：
--
作者：
Z. Hou;Yanxia Xing;Ai-Min Guo;Qing-feng Sun
研究了垂直磁场下二维导体/超导体混合系统中的交叉Andreev效应。考虑了石墨烯/超导体混合系统和电子气/超导体混合系统。结果表明，一个独特的交叉Andreev反射，与其他Andreev反射被完全抑制，是在一个高磁场中，因为在量子霍尔制度的手征边缘状态。重要的是，排他性交叉Andreev反射不仅适用于宽范围的系统参数，例如，系统的尺寸、中心超导体的宽度以及石墨烯和超导体之间的耦合质量，而且对无序非常鲁棒。当外加偏压在超导带隙内时，该系统可以实现高效率的库珀对分裂过程。
We study the crossed Andreev effects in two-dimensional conductor/superconductor hybrid systems under a perpendicular magnetic field. Both a graphene/superconductor hybrid system and an electron gas/superconductor one are considered. It is shown that an exclusive crossed Andreev reflection, with other Andreev reflections being completely suppressed, is obtained in a high magnetic field because of the chiral edge states in the quantum Hall regime. Importantly, the exclusive crossed Andreev reflection not only holds for a wide range of system parameters, e.g., the size of system, the width of central superconductor, and the quality of coupling between the graphene and the superconductor, but also is very robust against disorder. When the applied bias is within the superconductor gap, a robust Cooper-pair splitting process with high-efficiency can be realized in this system.