1. Investigation of Supercurrent in the Quantum Hall Regime in Graphene Josephson Junctions
- Author
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Takashi Taniguchi, Francois Amet, Russell Chamberlain, Ming-Tso Wei, Kenji Watanabe, Gleb Finkelstein, Yash Mehta, Andrew Seredinski, Ivan Borzenets, Michihisa Yamamoto, Anne Draelos, Chung-Ting Ke, and Seigo Tarucha
- Subjects
Josephson effect ,Superconductivity ,Materials science ,Condensed matter physics ,Condensed Matter - Mesoscale and Nanoscale Physics ,Graphene ,Supercurrent ,FOS: Physical sciences ,02 engineering and technology ,Edge (geometry) ,Quantum Hall effect ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,law.invention ,law ,0103 physical sciences ,Mesoscale and Nanoscale Physics (cond-mat.mes-hall) ,General Materials Science ,010306 general physics ,0210 nano-technology - Abstract
In this study, we examine multiple encapsulated graphene Josephson junctions to determine which mechanisms may be responsible for the supercurrent observed in the quantum Hall (QH) regime. Rectangular junctions with various widths and lengths were studied to identify which parameters affect the occurrence of QH supercurrent. We also studied additional samples where the graphene region is extended beyond the contacts on one side, making that edge of the mesa significantly longer than the opposite edge. This is done in order to distinguish two potential mechanisms: (a) supercurrents independently flowing along both non-contacted edges of graphene mesa, and (b) opposite sides of the mesa being coupled by hybrid electron–hole modes flowing along the superconductor/graphene boundary. The supercurrent appears suppressed in extended junctions, suggesting the latter mechanism.
- Published
- 2018