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arXiv · 1902.10575

Kerr-free three-wave mixing in superconducting quantum circuits

V. V. Sivak·N. E. Frattini·V. R. Joshi·A. Lingenfelter·S. Shankar·M. H. Devoret
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Abstract

Quantum-limited Josephson parametric amplifiers are crucial components in circuit QED readout chains. The dynamic range of state-of-the-art parametric amplifiers is limited by signal-induced Stark shifts that detune the amplifier from its operating point. Using a Superconducting Nonlinear Asymmetric Inductive eLement (SNAIL) as an active component, we show the ability to in situ tune the device flux and pump to a dressed Kerr-free operating point, which provides a 10-fold increase in the number of photons that can be processed by our amplifier, compared to the nominal working point. Our proposed and experimentally verified methodology of Kerr-free three-wave mixing can be extended to improve the dynamic range of other pumped operations in quantum superconducting circuits.

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V. V. Sivak, N. E. Frattini, V. R. Joshi, A. Lingenfelter, S. Shankar, M. H. Devoret. 2019-05-27. Kerr-free three-wave mixing in superconducting quantum circuits. https://doi.org/10.1103/physrevapplied.11.054060

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