Rhenium as a novel superconducting material for transmon qubits

ORAL

Abstract

Niobium and aluminum have been widely used to realize superconducting qubits. However, the native oxide at the metal air interface limits the qubit lifetime. This layer is highly disordered and it induces losses limiting the performances of the qubits. Recently, tantalum led to great improvement in qubit relaxation time by implementation. This improvement has been attributed to a thinner and less disordered oxide layer compared to Nb and Al. Here, for the first time, we demonstrate a new superconducting material platform: rhenium. Rhenium is more resistant to oxidation; it forms a thin oxide layer that is < 1 nm. We report statistics of T1 relaxation measurements of Re qubits, and compare the results to Nb qubits as well as Re encapsulated Nb qubits. Various transmon designs with varying participation ratios of interfaces and layers are used for these studies.

*This material is based upon work supported by the U.S. Department of Energy, Office of Science, National Quantum Information Science Research Centers, Superconducting Quantum Materials and Systems Center (SQMS) under contract number DE-AC02-07CH11359.

Presenters

  • Francesco Crisa

    • Fermi National Accelerator Laboratory
    • Illinois Institute of Technology, Fermilab
    • Illinois Institute of Technology

Authors

  • Francesco Crisa

    • Fermi National Accelerator Laboratory
    • Illinois Institute of Technology, Fermilab
    • Illinois Institute of Technology
  • Mustafa Bal

    • Fermilab
    • Fermi National Accelerator Laboratory
  • Shaojiang Zhu

    • Fermilab
    • Fermi National Accelerator Laboratory
  • Jae-Yel Lee

    • Fermi National Accelerator Laboratory
    • Fermilab
    • FermiLab
  • Akshay A Murthy

    • Fermilab
    • Fermi National Accelerator Laboratory
  • Anna Grassellino

    • Fermilab
    • Fermi National Accelerator Laboratory
  • Alexander Romanenko

    • Fermilab
    • Fermi National Accelerator Laboratory
  • John F Zasadzinski

    • Illinois Institute of Technology
    • Illinois Institute of Technology, Chicago, IL 60616, FNAL Superconducting Quantum Materials and Systems Center
  • Seth J Rice

    • Illinois Institute of Technology, Temple University
    • Illinois Institute of Technology, Chicago, IL 60616, Temple University, Philadelphia, PA, FNAL Superconducting Quantum Materials and Systems Center
    • Illinois Institute of Technology
  • Maria Iavarone

    • Temple University
    • Temple University, Philadelphia, PA, USA, FNAL Superconducting Quantum Materials and Systems Center
  • Sabrina Garattoni

    • Fermilab
    • FermiLab
    • Fermi National Accelerator Laboratory