Chiral quasiparticle tunneling between quantum Hall edges in proximity with a superconductor
Chiral quasiparticle tunneling between quantum Hall edges in proximity with a superconductor
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DOI：
10.1103/physrevb.100.121403
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发表时间：
2019-04
影响因子：
3.7
通讯作者：
M. Wei;A. Draelos;A. Seredinski;C. Ke;H. Li;Y. Mehta;K. Watanabe;T. Taniguchi;M. Yamamoto;S. Tarucha;G. Finkelstein;F. Amet;I. Borzenets
中科院分区：
文献类型：
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作者：
M. Wei;A. Draelos;A. Seredinski;C. Ke;H. Li;Y. Mehta;K. Watanabe;T. Taniguchi;M. Yamamoto;S. Tarucha;G. Finkelstein;F. Amet;I. Borzenets
我们研究了一个两端石墨烯约瑟夫森结，其接触形状形成一个狭窄的收缩，长度小于100 nm。接触由II型超导接触制成，并且能够承受足够高的磁场，以达到石墨烯中的量子霍尔（QH）制度。在这种情况下，器件电导由边缘状态加上收缩区的贡献决定。特别是，收缩区域可以支持高达~2.5T的超电流。此外，通过宽范围的磁场和栅极电压观察到增强的电导。这种额外的电导和超导电流的出现归因于沿着沿着相对的超导接触反向传播的量子霍尔边缘态之间的隧穿。
We study a two-terminal graphene Josephson junction with contacts shaped to form a narrow constriction, less than 100nm in length. The contacts are made from type II superconducting contacts and able to withstand magnetic fields high enough to reach the quantum Hall (QH) regime in graphene. In this regime, the device conductance is determined by edge states, plus the contribution from the constricted region. In particular, the constriction area can support supercurrents up to fields of ~2.5T. Moreover, enhanced conductance is observed through a wide range of magnetic fields and gate voltages. This additional conductance and the appearance of supercurrent is attributed to the tunneling between counter-propagating quantum Hall edge states along opposite superconducting contacts.