Decoherence of Majorana qubits by noisy gates

Manuel J. Schmidt, Diego Rainis, and Daniel Loss
Phys. Rev. B 86, 085414 – Published 7 August 2012

Abstract

We propose and study a realistic model for the decoherence of topological qubits, based on Majorana fermions in one-dimensional topological superconductors. The source of decoherence is the fluctuating charge on a capacitively coupled gate, modeled by noninteracting electrons. In this context, we clarify the role of quantum fluctuations and thermal fluctuations and find that quantum fluctuations do not lead to decoherence, while thermal fluctuations do. We explicitly calculate decay times due to thermal noise and give conditions for the gap size in the topological superconductor and the gate temperature. Based on this result, we provide simple rules for gate geometries and materials optimized for reducing the negative effect of thermal charge fluctuations on the gate.

  • Figure
  • Figure
  • Figure
  • Figure
  • Received 3 June 2012

DOI:https://doi.org/10.1103/PhysRevB.86.085414

©2012 American Physical Society

Authors & Affiliations

Manuel J. Schmidt

  • Institute for Theoretical Solid State Physics, RWTH Aachen, Sommerfeldstraße 26, 52056 Aachen, Germany

Diego Rainis and Daniel Loss

  • Department of Physics, University of Basel, Klingelbergstrasse 82, 4056 Basel, Switzerland

Article Text (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 86, Iss. 8 — 15 August 2012

Reuse & Permissions
Access Options

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review B

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×