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Constructing Functional Braids for Low-Leakage Topological Quantum Computing

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 نشر من قبل Haitan Xu
 تاريخ النشر 2008
  مجال البحث فيزياء
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We discuss how to significantly reduce leakage errors in topological quantum computation by introducing an irrelevant error in phase, using the construction of a CNOT gate in the Fibonacci anyon model as a concrete example. To be specific, we construct a functional braid in a six-anyon Hilbert space that exchanges two neighboring anyons while conserving the encoded quantum information. The leakage error is $sim$$10^{-10}$ for a braid of $sim$100 interchanges of anyons. Applying the braid greatly reduces the leakage error in the construction of generic controlled-rotation gates.



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