Fast and Accurate Design of Readout Resonators for Flip-Chip-Integrated Multi-Qubit Superconducting Quantum Processors

ORAL

Abstract

Predicting the parameters of superconducting resonators is important for achieving high qubit readout fidelity and preventing substantial Purcell decay. We use analytic equations, derived from conformal mapping, and 2D cross-sectional EM simulation, to calculate the frequency and coupling quality factor of resonators within a flip-chip geometry. We achieve a good agreement between this method and the more resource-intensive 3D FEM simulation under different inter-chip distances, considering the effective length due to the resonator-qubit coupling structure. Our method dramatically reduces the simulation time required for a multi-qubit quantum processor chip. We measured the inter-chip distance after flip-chip bonding to infer the resonators' capacitance and inductance. We show that the calculated resonator frequencies deviate from the measured values by less than 2%.

*We acknowledge the use of support and resources from Myfab Chalmers for device fabrication. This work is funded by the EU Flagship on Quantum Technology H2020-FETFLAG-2018-03 project 820363 OpenSuperQ and by the Knut and Alice Wallenberg (KAW) Foundation through the Wallenberg Centre for Quantum Technology (WACQT).

Presenters

  • Hang-Xi Li

    • Chalmers University of Technology

Authors

  • Hang-Xi Li

    • Chalmers University of Technology
  • Sandoko Kosen

    • Chalmers University of Technology
  • Marcus Rommel

    • Chalmers University of Technology
    • Chalmers Univ of Tech
  • Andreas Nylander

    • Chalmers University of Technology
  • Lert Chayanun

    • Chalmers University of Technology
  • Giovanna Tancredi

    • Chalmers University of Technology
    • Chalmers Univ of Tech
  • Kestutis Grigoras

    • VTT Technical Research Centre of Finland
    • VTT Technical Research Centre of Finland Ltd
    • VTT
  • Leif Grönberg

    • VTT Micro & Nanoelectronics
    • VTT Technical Research Centre of Finland
    • VTT Technical Research Centre of Finland Ltd
  • Liangyu Chen

    • Chalmers University of Technology
  • Marco Caputo

    • VTT Technical Research Centre of Finland
    • VTT Technical Research Centre of Finland Ltd
  • Alexey Zadorozhko

    • Chalmers University of Technology
  • Robert Rehammar

    • Chalmers University of Technology
  • Joonas Govenius

    • VTT Micro & Nanoelectronics
    • VTT Technical Research Centre of Finland
    • VTT Technical Research Centre of Finland Ltd
  • Daryoush Shiri

    • Chalmers University of Technology
  • Jonas Bylander

    • Chalmers Univ of Tech
    • Chalmers University of Technology