QFAST: Conflating Search and Numerical Optimization for Scalable Quantum Circuit Synthesis

  title={QFAST: Conflating Search and Numerical Optimization for Scalable Quantum Circuit Synthesis},
  author={Ed Younis and Koushik Sen and Katherine A. Yelick and Costin Iancu},
  journal={2021 IEEE International Conference on Quantum Computing and Engineering (QCE)},
  • Ed Younis, Koushik Sen, Costin Iancu
  • Published 12 March 2021
  • Computer Science
  • 2021 IEEE International Conference on Quantum Computing and Engineering (QCE)
We present a topology aware quantum synthesis algorithm designed to produce short circuits and to scale well in practice. The main contribution is a novel representation of circuits able to encode placement and topology using generic "gates", which allows the QFAST algorithm to replace expensive searches over circuit structures with few steps of numerical optimization. When compared against optimal depth, search based state-of-the-art techniques, QFAST produces comparable results: 1.19× longer… 
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