Mitigating coherent noise using Pauli conjugation

  title={Mitigating coherent noise using Pauli conjugation},
  author={Zhenyu Cai and Xiaosi Xu and Simon C. Benjamin},
  journal={npj Quantum Information},
Coherent noise can be much more damaging than incoherent (probabilistic) noise in the context of quantum error correction. One solution is to use twirling to turn coherent noise into incoherent Pauli channels. In this Article, we show that some of the coherence of the noise channel can actually be used to improve its logical fidelity by simply sandwiching the noise with a chosen pair of Pauli gates, which we call Pauli conjugation. Using the optimal Pauli conjugation, we can achieve a higher… 
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