Majorana qubit decoherence by quasiparticle poisoning

Diego Rainis; Daniel Loss

doi:10.1103/physrevb.85.174533

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arXiv · 1204.3326

Majorana qubit decoherence by quasiparticle poisoning

Diego Rainis·Daniel Loss

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Abstract

We consider the problem of quasiparticle poisoning in a nanowire-based realization of a Majorana qubit, where a spin-orbit-coupled semiconducting wire is placed on top of a (bulk) superconductor. By making use of recent experimental data exhibiting evidence of a low-temperature residual non-equilibrium quasiparticle population in superconductors, we show by means of analytical and numerical calculations that the dephasing time due to the tunneling of quasiparticles into the nanowire may be problematically short to allow for qubit manipulation.

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Diego Rainis, Daniel Loss. 2012-05-30. Majorana qubit decoherence by quasiparticle poisoning. https://doi.org/10.1103/physrevb.85.174533

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