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arXiv · 0802.4213

Constructing Functional Braids for Low-Leakage Topological Quantum Computing

Haitan Xu·Xin Wan
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Abstract

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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Haitan Xu, Xin Wan. 2008-10-13. Constructing Functional Braids for Low-Leakage Topological Quantum Computing. https://doi.org/10.1103/physreva.78.042325

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