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arXiv · 2409.05594

Super-Poissonian noise from quasiparticle poisoning in electron transport through a pair of Majorana bound states

Florinda Viñas Boström·Patrik Recher
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Abstract

Topological qubits based on non-abelian Majorana bound states (MBSs) are protected by parity which is challenged by quasiparticle poisoning (QPP). In this work, we show how QPP affects transport through a pair of coupled MBSs weakly connected to two current leads, using an open system approach and full counting statistics. We find that the correct low-energy physics requires to include next to leading order tunneling events in the coupling to the leads. In particular, our results show that QPP causes super-Poissonian local shot noise with a Fano factor that diverges with decreasing bias voltage, while the current and the non-local (cross-)noise are only little affected. We explain that these features are a direct consequence of the nature of MBSs being their own antiparticle making noise measurements a viable tool to search for MBSs in the presence of QPP.

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Florinda Viñas Boström, Patrik Recher. 2024-09-09. Super-Poissonian noise from quasiparticle poisoning in electron transport through a pair of Majorana bound states. https://doi.org/10.1103/m3gq-x86z

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