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arXiv · 2109.00994

Quantum design for advanced qubits: plasmonium

Feng-Ming Liu·Ming-Cheng Chen·Can Wang·Shao-Wei Li·Zhong-Xia Shang·Chong Ying·Jian-Wen Wang·Cheng-Zhi Peng·Xiaobo Zhu·Chao-Yang Lu·Jian-Wei Pan
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Abstract

The increasingly complex quantum electronic circuits with a number of coupled quantum degrees of freedom will become intractable to be simulated on classical computers, and requires quantum computers for an efficient simulation. In turn, it will be a central concept in quantum-aided design for next-generation quantum processors. Here, we demonstrate variational quantum eigensolvers to simulate superconducting quantum circuits with varying parameters covering a plasmon-transition regime, which reveals an advanced post-transmon qubit, "plasmonium". We fabricate this new qubit and demonstrate that it exhibits not only high single- and two-qubit gate fidelities (99.85(1)% and 99.58(3)%, respectively), but also a shrinking (by 60%) physical size and larger (by 50%) anharmonicity than the transmon, which can bring a number of advantages for scaling up multi-qubit devices. Our work opens the way to designing advanced quantum processors using existing quantum computing resources.

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Feng-Ming Liu, Ming-Cheng Chen, Can Wang, Shao-Wei Li, Zhong-Xia Shang, Chong Ying, Jian-Wen Wang, Cheng-Zhi Peng, Xiaobo Zhu, Chao-Yang Lu, Jian-Wei Pan. 2021-09-02. Quantum design for advanced qubits: plasmonium. https://arxiv.org/abs/2109.00994

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