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arXiv · 2010.05963

Majorana signatures in charge transport through a topological superconducting double-island system

Jukka I. Väyrynen·Dmitry I. Pikulin·Roman M. Lutchyn
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Abstract

We investigate the dynamics of a charge qubit consisting of two Coulomb-blockaded islands hosting Majorana zero modes. The frequency of the qubit is determined by coherent single-electron tunneling between two islands originating from the hybridization of two Majorana zero modes localized at the junction. We calculate the sequential tunneling current $I$ through the double-island device coupled to normal metal leads. We demonstrate that the $I\!-\!V$ characteristics in the large-bias regime can be used as a measurement of the coherent Majorana coupling $E_M$. We propose dc and ac transport experiments for measuring $E_M$, and discuss their limitations due to intrinsic dephasing mechanisms such as excited quasiparticles.

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Jukka I. Väyrynen, Dmitry I. Pikulin, Roman M. Lutchyn. 2020-10-12. Majorana signatures in charge transport through a topological superconducting double-island system. https://doi.org/10.1103/physrevb.103.205427

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