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arXiv · 2207.10687

Vortex-enabled Andreev processes in quantum Hall-superconductor hybrids

Yuchen Tang·Christina Knapp·Jason Alicea
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Abstract

Quantum Hall-superconductor heterostructures provide possible platforms for intrinsically fault-tolerant quantum computing. Motivated by several recent experiments that successfully integrated these phases, we investigate transport through a proximitized integer quantum Hall edge--paying particular attention to the impact of vortices in the superconductor. By examining the downstream conductance, we identify regimes in which sub-gap vortex levels mediate Andreev processes that would otherwise be frozen out in a vortex-free setup. Moreover, we show that at finite temperature, and in the limit of a large number of vortices, the downstream conductance can average to zero, indicating that the superconductor effectively behaves like a normal contact. Our results highlight the importance of considering vortices when using transport measurements to study superconducting correlations in quantum Hall-superconductor hybrids.

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Yuchen Tang, Christina Knapp, Jason Alicea. 2022-07-21. Vortex-enabled Andreev processes in quantum Hall-superconductor hybrids. https://doi.org/10.1103/physrevb.106.245411

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