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arXiv · 1808.03309

Braidonium: a braiding quantum circuit based on the $4π$ Josephson effect

John P. T. Stenger·Michael Hatridge·Sergey M. Frolov·David Pekker
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Abstract

We propose a topological qubit in which braiding and readout are mediated by the $4π$ Majorana-Josephson effect. The braidonium device consists of three Majorana nanowires that come together to make a tri-junction; in order to control the superconducting phase differences at the tri-junction the nanowires are enclosed in a ring made of a conventional superconductor; and in order to perform initialization/readout one of the nanowires is coupled to a fluxonium qubit through a topological Josephson junction. We analyze how flux-based control and readout protocols can be used to demonstrate braiding and qubit operation for realistic materials and circuit parameters.

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John P. T. Stenger, Michael Hatridge, Sergey M. Frolov, David Pekker. 2019-01-22. Braidonium: a braiding quantum circuit based on the $4π$ Josephson effect. https://doi.org/10.1103/physrevb.99.035307

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