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arXiv · 2306.07696

Crossed Andreev reflection and elastic co-tunneling in a three-site Kitaev chain nanowire device

Alberto Bordin·Xiang Li·David van Driel·Jan Cornelis Wolff·Qingzhen Wang·Sebastiaan L. D. ten Haaf·Guanzhong Wang·Nick van Loo·Leo P. Kouwenhoven·Tom Dvir
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Abstract

The formation of a topological superconducting phase in a quantum-dot-based Kitaev chain requires nearest neighbor crossed Andreev reflection and elastic co-tunneling. Here we report on a hybrid InSb nanowire in a three-site Kitaev chain geometry - the smallest system with well-defined bulk and edge - where two superconductor-semiconductor hybrids separate three quantum dots. We demonstrate pairwise crossed Andreev reflection and elastic co-tunneling between both pairs of neighboring dots and show sequential tunneling processes involving all three quantum dots. These results are the next step towards the realization of topological superconductivity in long Kitaev chain devices with many coupled quantum dots.

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Alberto Bordin, Xiang Li, David van Driel, Jan Cornelis Wolff, Qingzhen Wang, Sebastiaan L. D. ten Haaf, Guanzhong Wang, Nick van Loo, Leo P. Kouwenhoven, Tom Dvir. 2023-06-13. Crossed Andreev reflection and elastic co-tunneling in a three-site Kitaev chain nanowire device. https://doi.org/10.1103/physrevlett.132.056602

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