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arXiv · 2602.14333

High-fidelity Quantum Readout Processing via an Embedded SNAIL Amplifier

Leon Bello·Boris Mesits·Michael Hatridge·Hakan E. Türeci
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Abstract

Scalable, high-fidelity quantum-state readout remains a central challenge in the development of large-scale superconducting quantum processors. Conventional dispersive readout architectures depend on bulky isolators and external amplifiers, introducing significant hardware overhead and limiting opportunities for on-chip information processing. In this work, we propose a novel approach that embeds a nonlinear Superconducting Nonlinear Asymmetric Inductive eLement (SNAIL) into the readout chain, enabling coherent and directional processing of readout signals directly on-chip. This embedded SNAIL platform allows frequency-multiplexed resonators to interact through engineered couplings, forming a tunable readout-amplifier-output architecture that can manipulate quantum readout data \textit{in situ}. Through theoretical modeling and numerical optimization, we show that this platform enhances fidelity, suppresses measurement-induced decoherence, and simplifies hardware complexity. These results establish the hybridized SNAIL as a promising building block for scalable and coherent quantum-state readout in next-generation processors.

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Leon Bello, Boris Mesits, Michael Hatridge, Hakan E. Türeci. 2026-02-15. High-fidelity Quantum Readout Processing via an Embedded SNAIL Amplifier. https://arxiv.org/abs/2602.14333

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