Time domain measurement of on-chip flux waveforms for superconducting qubits

ORAL

Abstract

Implementing high fidelity entangling gates between frequency-tunable superconducting qubits often requires ad hoc optimization of control waveforms on a per-channel basis due to signal path irregularities. To better model these irregularities and more efficiently optimize control waveforms, we have developed a method of directly measuring flux waveforms on-chip using a low Q tunable resonator. This device may be operated in two regimes--one with a high sensitivity to flux, used to characterize DC to ~500 MHz current waveforms, and another which can can provide an estimate of the worst standing wave amplitude in a microwave chain. Through A/B comparisons, this technique provides an avenue for measuring the transfer function of specific signal chain components in a cryogenic environment avoiding both the complication of measuring qubits and the limits of their coherence time.

Presenters

  • Brooks Foxen

    • UC Santa Barbara
    • Univ of California - Santa Barbara
    • University of California - Santa Barbara
    • Physics, University of California, Santa Barbara

Authors

  • Brooks Foxen

    • UC Santa Barbara
    • Univ of California - Santa Barbara
    • University of California - Santa Barbara
    • Physics, University of California, Santa Barbara
  • Zijun Chen

    • Physics, Univ of California - Santa Barbara
    • UC Santa Barbara
    • Univ of California - Santa Barbara
    • UCSB
    • Google
  • Ben Chiaro

    • Physics, Univ of California - Santa Barbara
    • UC Santa Barbara
    • Univ of California - Santa Barbara
    • UCSB
    • University of California - Santa Barbara
    • Physics, University of California, Santa Barbara
  • Andrew Dunsworth

    • Physics, Univ of California - Santa Barbara
    • UC Santa Barbara
    • Univ of California - Santa Barbara
    • UCSB
    • University of California - Santa Barbara
    • Physics, University of California, Santa Barbara
  • Charles Neill

    • Physics, Univ of California - Santa Barbara
    • UC Santa Barbara
    • Univ of California - Santa Barbara
    • UCSB
    • Physics, University of California, Santa Barbara
  • Jim Wenner

    • UC Santa Barbara
  • John Martinis

    • Google
    • Google Inc - Santa Barbara
    • Google Inc.
    • UC Santa Barbara and Google