A Dynamically Reconfigurable Quantum Processor Architecture*

Despite recent improvements in two-qubit gate fidelities in superconducting qubit architectures, the entangling of distant qubits still requires cascading multiple nearest neighbor two-qubit gates, so the overall compound error rate grows exponentially with the distance between the qubits on the connectivity graph. We seek to combine the controllability of superconducting quantum circuits with the flexibility of the all-to-all qubit connectivity graphs experimentally demonstrated in AMO experiments. Here we propose our scheme to utilize 3D integration techniques and parametric coupling in building a high-performance 3D QPU with programmable arbitrary qubit connectivity enabled by the chip architecture. Our scheme employs a squid tunable multimode bus resonator coupled to all of the qubits to enable the parametric coupling. By using a single chip scale bus resonator to couple all qubits we transfer the reconfigurability complexity to the room temperature electronics where multiplexed microwave signals control the qubit connectivity graph.