报告时间：2023年9月8日（星期五）下午14:00

报告地点：物质科研楼C404会议室

报告题目：Native approach to controlled-Z gates in inductively coupled fluxonium qubits

报告摘要：

The fluxonium qubits have emerged as a promising platform for gate-based quantum information processing. However, their extraordinary protection against charge fluctuations comes at a cost: when coupled capacitively, the qubit-qubit interactions are restricted to XX-interactions. Consequently, effective XX- or XZ-interactions are only constructed either by temporarily populating higher-energy states, or by exploiting perturbative effects under microwave driving. Instead, we propose and demonstrate an inductive coupling scheme, which offers a wide selection of native qubit-qubit interactions for fluxonium. In particular, we leverage a built-in, flux-controlled ZZ-interaction to perform qubit entanglement. To combat the increased flux-noise-induced dephasing away from the flux-insensitive position, we use a continuous version of the dynamical decoupling scheme to perform noise filtering. Combining these, we demonstrate a 20 ns controlled-Z (CZ) gate with a mean fidelity of 99.53%. More than confirming the efficacy of our gate scheme, this high-fidelity result also reveals a promising but rarely explored parameter space uniquely suitable for gate operations between fluxonium qubits.

报告人简介：

马希铮博士，2020年毕业于University of Colorado，导师Prof. Konrad W. Lehnert。博士期间从事微纳机械振子和超导量子比特杂化系统的实验研究，相关工作发表在Nature Physics, Physical Review Letters等期刊上。现任职于阿里巴巴量子实验室，负责超导量子比特芯片的高精度门操作等研究。