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arXiv · 1607.04638

Dynamically Correcting a CNOT Gate for any Systematic Logical Error

Fernando A. Calderon-Vargas·J. P. Kestner
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Abstract

We derive a set of composite pulse sequences that generates CNOT gates and correct all systematic errors within the logical subspace to arbitrary order. These sequences are applicable for any two-qubit interaction Hamiltonian, and make no assumptions about the underlying noise mechanism except that it is constant on the timescale of the operation. We do assume access to error-free single-qubit gates, so single-qubit gate imperfections eventually limit the achievable fidelity. However, since single-qubit gates generally have much higher fidelities than two-qubit gates in practice, these pulse sequences offer useful dynamical correction for a wide range of coupled qubit systems.

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Fernando A. Calderon-Vargas, J. P. Kestner. 2017-04-10. Dynamically Correcting a CNOT Gate for any Systematic Logical Error. https://doi.org/10.1103/physrevlett.118.150502

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