Nonlocal connectivity is a critical resource for universal logical quantum gates and low-overhead quantum error correction codes, and is unavailable on current superconducting devices with nearest-neighbor connections. To rectify the deficiency in connectivity of superconducting circuit systems, we experimentally demonstrate a convenient on-chip coupler of centimeters length and with quality factor close to $1\times {10}^6$. The entangling gate is performed between two fluxonium qubits, reaching a fidelity of 99.37% within 120 ns, while the system static $ZZ$ interaction rate remains as low as 144 Hz without active cancellation or circuit parameter targeting. This high-fidelity low-crosstalk nonlocal coupler can be the building block of a binary-tree connectivity graph, reducing the average qubit entangling distance from $O(N)$ to $O({\log }_2N)$. With the high-fidelity nonlocal entanglement, novel quantum algorithms can be implemented on the superconducting qubit system, positioning it as a strong competitor to other physics systems regarding circuit connectivity.

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• Optoelectronics
• Quantum circuits
• Quantum control
• Quantum error correction
• Quantum gates
• Quantum information with solid state qubits
• Superconducting devices
• Microwave techniques