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arXiv · 1601.07369

Time scales for Majorana manipulation using Coulomb blockade in gate-controlled superconducting nanowires

Michael Hell·Jeroen Danon·Karsten Flensberg·Martin Leijnse
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Abstract

We numerically compute the low-energy spectrum of a gate-controlled superconducting topological nanowire segmented into two islands, each Josephson-coupled to a bulk superconductor. This device may host two pairs of Majorana bound states and could provide a platform for testing Majorana fusion rules. We analyze the crossover between (i) a charge-dominated regime utilizable for initialization and readout of Majorana bound states, (ii) a single-island regime for dominating inter-island Majorana coupling, (iii) a Josephson-plasmon regime for large coupling to the bulk superconductors, and (iv) a regime of four Majorana bound states allowing for topologically protected Majorana manipulations. From the energy spectrum, we derive conservative estimates for the time scales of a fusion-rule testing protocol proposed recently [arXiv:1511.05153]. We also analyze the steps needed for basic Majorana braiding operations in branched nanowire structures.

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Michael Hell, Jeroen Danon, Karsten Flensberg, Martin Leijnse. 2016-01-27. Time scales for Majorana manipulation using Coulomb blockade in gate-controlled superconducting nanowires. https://doi.org/10.1103/physrevb.94.035424

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