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arXiv · 2304.06754

Non-Abelian holonomy of Majorana zero modes coupled to a chaotic quantum dot

Max Geier·Svend Krøjer·Felix von Oppen·Charles M. Marcus·Karsten Flensberg·Piet W. Brouwer
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Abstract

If a quantum dot is coupled to a topological superconductor via tunneling contacts, each contact hosts a Majorana zero mode in the limit of zero transmission. Close to a resonance and at a finite contact transparency, the resonant level in the quantum dot couples the Majorana modes, but a ground state degeneracy per fermion parity subspace remains if the number of Majorana modes coupled to the dot is five or larger. Upon varying shape-defining gate voltages while remaining close to resonance, a nontrivial evolution within the degenerate ground-state manifold is achieved. We characterize the corresponding non-Abelian holonomy for a quantum dot with chaotic classical dynamics using random matrix theory and discuss measurable signatures of the non-Abelian time-evolution.

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Max Geier, Svend Krøjer, Felix von Oppen, Charles M. Marcus, Karsten Flensberg, Piet W. Brouwer. 2023-04-13. Non-Abelian holonomy of Majorana zero modes coupled to a chaotic quantum dot. https://doi.org/10.1103/physrevlett.132.036604

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