Simulating Large Quantum Circuits on a Small Quantum Computer.

@article{Peng2020SimulatingLQ,
  title={Simulating Large Quantum Circuits on a Small Quantum Computer.},
  author={Tianyi Peng and Aram Wettroth Harrow and Maris A. Ozols and Xiaodi Wu},
  journal={Physical review letters},
  year={2020},
  volume={125 15},
  pages={
          150504
        }
}
Limited quantum memory is one of the most important constraints for near-term quantum devices. Understanding whether a small quantum computer can simulate a larger quantum system, or execute an algorithm requiring more qubits than available, is both of theoretical and practical importance. In this Letter, we introduce cluster parameters K and d of a quantum circuit. The tensor network of such a circuit can be decomposed into clusters of size at most d with at most K qubits of inter-cluster… 

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