Demonstration of Dynamically Reconfigurable Long-Range Photon Exchange in a Multi-Qubit Superconducting Quantum Processor

We propose and demonstrate a quantum processor (QPU) architecture using superconducting qubits with a reconfigurable qubit connectivity graph. Transverse interactions can be generated between arbitrary pairs of qubits in the QPU with the connectivity graph encoded by the room temperature microwave controls. The reconfigurability is enabled by tunable, time dependent couplings between qubits and a shared tunable Bus resonator (Bus). We implement an 8-qubit version of the proposed architecture and find good agreement between circuit theory predictions and experimental behavior of the tunable Bus element. Qubit-Bus parametric coupling of up to 8MHz is achieved. We further demonstrate qubit-qubit interactions mediated by the Bus within a 5-qubit subset of the device with a maximum coupling rate 0.9MHz and separation of 9.2cm along the Bus resonator. Our work sheds light on opportunities to realize highly connected, reconfigurable QPUs in superconducting circuits.