arXiv:1307.5162 · Physical Review Letters

Protected Quantum Computing: Interleaving Gate Operations with Dynamical Decoupling Sequences

Jingfu Zhang, Alexandre M. Souza, Frederico Dias Brandao, Dieter Suter

Published Feb 6, 2014• 109 citations

Abstract

Implementing precise operations on quantum systems is one of the biggest challenges for building quantum devices in a noisy environment. Dynamical decoupling attenuates the destructive effect of the environmental noise, but so far, it has been used primarily in the context of quantum memories. Here, we experimentally demonstrate a general scheme for combining dynamical decoupling with quantum logical gate operations using the example of an electron-spin qubit of a single nitrogen-vacancy center in diamond. We achieve process fidelities >98% for gate times that are 2 orders of magnitude longer than the unprotected dephasing time T2.

DOI: 10.1103/physrevlett.112.050502

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