High-speed $R_{ZZ}$ gates in Kerr-cat qubits via fast-forward scaling

Takaaki Aoki; Shumpei Masuda

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arXiv · 2511.11056

High-speed $R_{ZZ}$ gates in Kerr-cat qubits via fast-forward scaling

Takaaki Aoki·Shumpei Masuda

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Abstract

Kerr parametric oscillators can encode Kerr-cat qubits, whose biased-noise nature can reduce the hardware overhead required for fault-tolerant quantum computation. In a recently proposed $R_{ZZ}$-gate scheme for Kerr-cat qubits, a tunable coupler must be displaced while avoiding nonadiabatic excitation. To address this challenge, we propose and theoretically analyze a protocol that applies fast-forward scaling to the coupler displacement. The protocol suppresses nonadiabatic excitation of the coupler and enables high speed $R_{ZZ}$ gates.

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Takaaki Aoki, Shumpei Masuda. 2025-11-14. High-speed $R_{ZZ}$ gates in Kerr-cat qubits via fast-forward scaling. https://arxiv.org/abs/2511.11056

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