First-principles analysis of cross-resonance gate operation

@article{Malekakhlagh2020FirstprinciplesAO,
  title={First-principles analysis of cross-resonance gate operation},
  author={Moein Malekakhlagh and Easwar Magesan and David C. McKay},
  journal={Physical Review A},
  year={2020}
}
We present a comprehensive theoretical study of the cross-resonance gate operation covering estimates for gate parameters and gate error as well as analyzing spectator qubits and multi-qubit frequency collisions. We start by revisiting the derivation of effective Hamiltonian models following Magesan et al. (arXiv:1804.04073). Transmon qubits are commonly modeled as a weakly anharmonic Kerr oscillator. Kerr theory only accounts for qubit frequency renormalization, while adopting number states as… 
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