论文标题
使用强助剂调制的快速高保真门，用于循环耦合的磁盘
Fast high-fidelity gates for galvanically-coupled fluxonium qubits using strong flux modulation
论文作者
论文摘要
长时间的连贯性时间，大的非谐和性和稳健的电荷无敏感性使Fluxonium Qubits成为传输的有趣替代品。最近的实验证明了低频Fluxonia的创纪录相干时间。在这里，我们提出了一种使用Flux-Tunable $ \ textIt {xx} $耦合的电流耦合方案。要实现高保真纠缠$ \ sqrt {i \ mathrm {swap}} $ GATE，我们调节此耦合的强度，并设计可变的时间身份门以同步所需的单Qubit操作。两种类型的门都是使用强大的AC通量驱动器实现的，仅持续几个驱动器。我们采用了一个理论框架，能够按照这种强驱动器的要求捕获超出旋转波近似（RWA）的量子动力学。我们预测$ \ sqrt {i \ mathrm {swap}} $ GATE在现实条件下的开放系统保真度为$ f> 0.999 $。
Long coherence times, large anharmonicity and robust charge-noise insensitivity render fluxonium qubits an interesting alternative to transmons. Recent experiments have demonstrated record coherence times for low-frequency fluxonia. Here, we propose a galvanic-coupling scheme with flux-tunable $\textit{XX}$ coupling. To implement a high-fidelity entangling $\sqrt{i\mathrm{SWAP}}$ gate, we modulate the strength of this coupling and devise variable-time identity gates to synchronize required single-qubit operations. Both types of gates are implemented using strong ac flux drives, lasting for only a few drive periods. We employ a theoretical framework capable of capturing qubit dynamics beyond the rotating-wave approximation (RWA) as required for such strong drives. We predict an open-system fidelity of $F>0.999$ for the $\sqrt{i\mathrm{SWAP}}$ gate under realistic conditions.
