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arXiv · 2512.11756

CNOT gates in inductively coupled multi-fluxonium systems

Valeria Díaz Moreno·Nikola D. Dimitrov·Vladimir E. Manucharyan·Maxim G. Vavilov
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Abstract

High-fidelity two-qubit gates have been demonstrated in systems of two fluxonium qubits; however, the realization of scalable quantum processors requires maintaining low error rates in substantially larger architectures. In this work, we analyze a system of four inductively coupled fluxonium qubits to determine the impact of spectator qubits on the performance of a \textsc{cnot} gate. Our results show that spectator-induced errors are strongly suppressed when the transition frequencies of the spectator qubits are sufficiently detuned from those of the active qubits. We identify favorable frequency configurations for the four-qubit chain that yield \textsc{cnot} gate errors below $10^{-4}$ for gate times shorter than 100 ns. Leveraging the locality of the nearest-neighbor coupling, we extrapolate our findings to longer fluxonium chains, suggesting a viable path toward scalable, low-error quantum information processing.

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Valeria Díaz Moreno, Nikola D. Dimitrov, Vladimir E. Manucharyan, Maxim G. Vavilov. 2025-12-12. CNOT gates in inductively coupled multi-fluxonium systems. https://arxiv.org/abs/2512.11756

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