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arXiv · 1703.10226

Encrypting Majorana Fermions-qubits as Bound States in the Continuum

L. H. Guessi·F. A. Dessotti·Y. Marques·L. S. Ricco·G. M. Pereira·P. Menegasso·M. de Souza·A. C. Seridonio
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Abstract

We theoretically investigate a topological Kitaev chain connected to a double quantum-dot (QD) setup hybridized with metallic leads. In this system we observe the emergence of two striking phenomena: (i) a decrypted Majorana fermion (MF) qubit recorded over a single QD, which is detectable by means of conductance measurements due to the asymmetrical MF-qubit leaked state into the QDs; (ii) an encrypted qubit recorded in both QDs when the leakage is symmetrical. In such a regime, we have a cryptographylike manifestation, since the MF qubit becomes bound states in the continuum, which is not detectable in conductance experiments.

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L. H. Guessi, F. A. Dessotti, Y. Marques, L. S. Ricco, G. M. Pereira, P. Menegasso, M. de Souza, A. C. Seridonio. 2017-03-29. Encrypting Majorana Fermions-qubits as Bound States in the Continuum. https://doi.org/10.1103/physrevb.96.041114

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