Variational quantum gate optimization on superconducting qubit system

ORAL

Abstract

Hybrid quantum-classical (HQC) algorithms aim at realizing the quantum advantage in shallow depth quantum circuits with an aid of classical computation. Recently, HQC algorithms have been extensively studied with the expectation that they may solve practical problems in the near future. However, the quantum gate fidelities directly limit the sizes of executable problems in quantum computers without quantum error correction. While HQC algorithms require fewer quantum gates, the state-of-the-art gate fidelities are still insufficient to deal with practical problems. In this presentation, we propose a gate optimization method, where high-fidelity multi-qubit gates are generated by optimizing parametrized quantum circuits consisting of tunable high-fidelity single-qubit gates and fixed multi-qubit gates with limited controllability. We call the method variational quantum gate optimization (VQGO) and demonstrate it on a superconducting qubit system.

*This work is partly supported by JST ERATO (JPMJER1601) and MEXT Q-LEAP (JPMXS0118068682).

Presenters

  • Kentaro Heya

    • Research Center for Advanced Science and Technology, The University of Tokyo
    • Univ of Tokyo

Authors

  • Kentaro Heya

    • Research Center for Advanced Science and Technology, The University of Tokyo
    • Univ of Tokyo
  • Yasunari Suzuki

    • NTT Secure Platform Laboratories, NTT Corporation
  • Yutaka Takeda

    • Research Center for Advanced Science and Technology, The University of Tokyo
  • Akhil Prataps Singh

    • Research Center for Advanced Science and Technology, The University of Tokyo
  • Shingo Kono

    • Center for Emergent Matter Science, RIKEN
    • CEMS, RIKEN
    • RIKEN
  • Koh-ichi Nittoh

    • Center for Emergent Matter Science, RIKEN
  • Koichi Kusuyama

    • Center for Emergent Matter Science, RIKEN
  • Shuhei Tamate

    • Research Center for Advanced Science and Technology, The University of Tokyo
    • The University of Tokyo
  • Yutaka Tabuchi

    • Research Center for Advanced Science and Technology, The University of Tokyo
    • The University of Tokyo
  • Keisuke Fujii

    • Graduate School of Engineering Science, Osaka University
    • Department of Systems Innovation, Graduate School of Engineering Science, Osaka University
    • Osaka University
    • Osaka Univ
  • Yasunobu Nakamura

    • Research Center for Advanced Science and Technology, The University of Tokyo
    • Univ of Tokyo
    • RIKEN
    • RCAST, The University of Tokyo
    • The University of Tokyo