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Proposal for a scalable charging-energy-protected topological qubit in a quantum spin Hall system

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 نشر من قبل Dmitry Pikulin
 تاريخ النشر 2020
  مجال البحث فيزياء
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 تأليف Dmitry I. Pikulin




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The quantum spin Hall edge is predicted to reliably produce Majorana zero modes on the border between magnetic insulator- and superconductor-proximitized regions of the edge. The direction of magnetization determines the size of the induced magnetic gap and can control the resulting tunnel barrier. Here we propose a way to avoid magnetic manipulations of the material and use electric-only local control of the barrier. We follow with a design of a charging-energy-protected qubit and a layout of a quantum computer based on the quantum spin Hall effect. We estimate relevant scales and show that they allow for testing of these ideas in the near future.



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