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arXiv · 1705.09364

Low-field Topological Threshold in Majorana Double Nanowires

Constantin Schrade·Manisha Thakurathi·Christopher Reeg·Silas Hoffman·Jelena Klinovaja·Daniel Loss
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Abstract

A hard proximity-induced superconducting gap has recently been observed in semiconductor nanowire systems at low magnetic fields. However, in the topological regime at high magnetic fields, a soft gap emerges and represents a fundamental obstacle to topologically protected quantum information processing with Majorana bound states. Here we show that in a setup of double Rashba nanowires that are coupled to an s-wave superconductor and subjected to an external magnetic field along the wires, the topological threshold can be significantly reduced by the destructive interference of direct and crossed-Andreev pairing in this setup, precisely down to the magnetic field regime in which current experimental technology allows for a hard superconducting gap. We also show that the resulting Majorana bound states exhibit sufficiently short localization lengths, which makes them ideal candidates for future braiding experiments.

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Constantin Schrade, Manisha Thakurathi, Christopher Reeg, Silas Hoffman, Jelena Klinovaja, Daniel Loss. 2017-05-25. Low-field Topological Threshold in Majorana Double Nanowires. https://doi.org/10.1103/physrevb.96.035306

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