Calderon-Vargas F A, Kestner J P
Department of Physics, University of Maryland Baltimore County, Baltimore, Maryland 21250, USA.
Phys Rev Lett. 2017 Apr 14;118(15):150502. doi: 10.1103/PhysRevLett.118.150502. Epub 2017 Apr 10.
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 time scale of the operation. We do assume access to high-fidelity 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.