Superconducting Traveling-Wave Kinetic Inductance Amplifiers Based on Self-Aligned Technology

ORAL

Abstract

We realize traveling-wave kinetic inductance (KIT) amplifiers based on thin superconducting transmission lines. The nonlinearity originates from the kinetic inductance of the superconducting material and enables amplification. Often, the impedance of the transmission line is significantly higher than the 50 Ohm microwave environment due to the dominance of kinetic inductance over geometric inductance at micron size scales. To address this impedance mismatch, we employ a novel self-aligned technology to fabricate coplanar waveguide and LC ladder transmission lines using optical lithography in NbTiN, TiN, and NbN. This technology allows transmission lines with very narrow gaps and center lines, down to 200 nm, enabling tunable impedance over a broad range and suppression of unwanted slotline modes. Measurements of parametric gain in resulting transmission lines, and qubits will be presented.

–

Presenters

  • Mustafa Bal

    NIST - Boulder

Authors

  • Mustafa Bal

    NIST - Boulder

  • Xian Wu

    NIST - Boulder, National Institute of Standards and Technology

  • Russell Lake

    National Institute of Standards and Technology, NIST - Boulder, NIST, QCD Labs, Department of Applied Physics, Aalto University

  • Junling Long

    National Institute of Standards and Technology, NIST - Boulder, NIST

  • Hsiang-Sheng Ku

    National Institute of Standards and Technology, NIST - Boulder

  • David Pappas

    NIST, National Institute of Standards and Technology, NIST - Boulder