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arXiv · 2408.06154

Lumped-element two-section impedance-matched SNAIL parametric amplifier

D. Moskaleva·N. Smirnov·D. Moskalev·A. Ivanov·A. Matanin·D. Baklykov·M. Teleganov·V. Polozov·V. Echeistov·E. Malevannaya·I. Korobenko. A. Kuguk·G. Nikerov·J. Agafonova·I. Rodionov
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Abstract

Broadband impedance-matched Josephson parametric amplifiers are key components for high-fidelity single-shot multi-qubit readout. Nowadays, several types of impedance matched parametric amplifiers have been proposed: the first is an impedance-matched parametric amplifier based on a Klopfenstein taper, and the second is an impedance-matched parametric amplifier based on auxiliary resonators. Here, we present the quantum-limited 3-wave-mixing lumped-element SNAIL parametric amplifier with two-units impedance matching transformer. A two-pole Chebyshev matching network with shunted resonators based on parallel-plate capacitors and superconducting planar coil. Operating in a flux-pumped mode, we experimentally demonstrate an average gain of $15dB$ across a $600MHz$ bandwidth, along with an average saturation power of $-107dBm$ and quantum-limited noise temperature.

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D. Moskaleva, N. Smirnov, D. Moskalev, A. Ivanov, A. Matanin, D. Baklykov, M. Teleganov, V. Polozov, V. Echeistov, E. Malevannaya, I. Korobenko. A. Kuguk, G. Nikerov, J. Agafonova, I. Rodionov. 2024-08-12. Lumped-element two-section impedance-matched SNAIL parametric amplifier. https://arxiv.org/abs/2408.06154

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