Reducing the CNOT count for Clifford+T circuits on NISQ architectures

  title={Reducing the CNOT count for Clifford+T circuits on NISQ architectures},
  author={Vlad Gheorghiu and Jiaxin Huang and Sarah Meng Li and Michele Mosca and Priyanka Mukhopadhyay},
  journal={IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems},
While mapping a quantum circuit to the physical layer one has to consider the numerous constraints imposed by the underlying hardware architecture. Connectivity of the physical qubits is one such constraint that restricts two-qubit operations such as CNOT to "connected" qubits. SWAP gates can be used to place the logical qubits on admissible physical qubits, but they entail a significant increase in CNOT-count, considering the fact that each SWAP gate can be implemented by 3 CNOT gates. In… 

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