In superconducting quantum circuits, decoherence errors in qubits constitute a critical factor limiting quantum gate performance. To mitigate decoherence-induced gate infidelity, rapid implementation of quantum gates is essential. Here we propose a scheme for rapid controlled-$Z$ (CZ) gate implementation through energy-level engineering, which leverages Rabi oscillations between the $|11\rangle$ state and the noncomputational state in a tunable-coupler architecture. Numerical simulations achieved a 22-ns nonadiabatic CZ gate with fidelity greater than $99.99\%$. We further investigated the performance of the CZ gate in the presence of anharmonicity offsets. The results demonstrate that a high-fidelity CZ gate with an error rate below ${10}^{-4}$ remains achievable even with finite anharmonicity variations. Furthermore, the detrimental impact of spectator qubits in different quantum states on the fidelity of the CZ gate is effectively suppressed by incorporating a tunable coupler. This scheme exhibits potential for extending the circuit execution depth constrained by coherence time limitations.

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• Quantum computation
• Quantum gates
• Quantum information processing