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Low-Weight Pauli Hamiltonian Sequences for Noise-Resilient Quantum Gates

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 Added by Ryan Epstein
 Publication date 2017
  fields Physics
and research's language is English




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A simple protocol based on low-weight Pauli Hamiltonians is introduced for performing quantum gates that are robust to control noise. Gates are implemented by an adiabatic sequence of single-qubit fields and two-qubit interactions with a single ancillary qubit, whereas related techniques require three-qubit interactions, perturbation gadgets, higher dimensional subsystems, and/or more ancilla qubits. Low-weight interactions and low qubit overhead open a viable path to experimental investigation, while operation in a degenerate ground space allows for physical qubit designs that are immune to energy relaxation. Simulations indicate that two-qubit gate error due to control noise can be as low as $10^{-5}$, for realizable coupling strengths and time-scales, with low-frequency noise that is as high as 15% of the control pulse amplitude.

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