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arXiv · 1809.11048

Kinetic Inductance Traveling Wave Amplifiers For Multiplexed Qubit Readout

Leonardo Ranzani·Mustafa Bal·Kin Chung Fong·Guilhem Ribeill·Xian Wu·Junling Long·Hsiang Sheng Ku·Robert P. Erickson·David Pappas·Thomas A. Ohki
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Abstract

We describe a kinetic inductance traveling-wave (KIT) amplifier suitable for superconducting quantum information measurements and characterize its wideband scattering and noise properties. We use mechanical microwave switches to calibrate the four amplifier scattering parameters up to the device input and output connectors at the dilution refrigerator base temperature and a tunable temperature load to characterize the amplifier noise. Finally, we demonstrate the high fidelity simultaneous dispersive readout of two superconducting transmon qubits. The KIT amplifier provides low-noise amplification of both readout tones with readout fidelities of 83% and 89% and negligible effect on qubit lifetime and coherence.

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Leonardo Ranzani, Mustafa Bal, Kin Chung Fong, Guilhem Ribeill, Xian Wu, Junling Long, Hsiang Sheng Ku, Robert P. Erickson, David Pappas, Thomas A. Ohki. 2018-09-28. Kinetic Inductance Traveling Wave Amplifiers For Multiplexed Qubit Readout. https://doi.org/10.1063/1.5063252

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