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arXiv · 2601.01826

Global Parametric Gates for Multi-qubit Entanglement

Jize Yang·Lin Guo·Haonan Xiong·Jiahui Wang·Yan Li·Yunfan Yang·Chenjie An·Hongyi Zhang·Luyan Sun·Yipu Song·Luming Duan
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Abstract

We propose and experimentally demonstrate a global parametric gate that generates multi-qubit entangled states in a single step. By applying a parametric drive to a common qubit at precise detunings relative to computational qubits, we directly produce two-, three-, and four-qubit entanglement with state fidelities of 99.4\%\pm0.2\%, 93.4\%\pm0.3\%, and 91.4\%\pm0.3\%, respectively. This scheme enables efficient, reconfigurable control using only microwave drives and is compatible with fixed-frequency qubits. Error analyses indicate that infidelity stems primarily from decoherence and coherent control errors, with negligible contributions from static ZZ coupling and flux noise. Furthermore, simulations with state-of-the-art parameters predict this global gate can generate high-fidelity (99.70\%) entanglement in systems of up to six qubits.

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Jize Yang, Lin Guo, Haonan Xiong, Jiahui Wang, Yan Li, Yunfan Yang, Chenjie An, Hongyi Zhang, Luyan Sun, Yipu Song, Luming Duan. 2026-01-05. Global Parametric Gates for Multi-qubit Entanglement. https://arxiv.org/abs/2601.01826

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