Tunable coupling of widely separated superconducting qubits: A possible application toward a modular quantum device

Besides striving to assemble more and qubits in a single monolithic quantum device, taking modular design strategy may mitigate numerous engineering challenges for achieving large-scalable processors with superconducting qubits. Nevertheless, major challenge the device is how realize high-fidelity entanglement operations on housed different modules while preserving desired isolation between modules. In this work, we propose conceptual of where nearby are spatially separated by centimeters. principle, each module can contain tens qubits, be separately fabricated, characterized, packaged, replaced. By introducing bridge qubit coupling scheme utilizing tunable bus, that modules, could realized. Given physically reasonable assumptions, expect sub-100-ns two-qubit gates which than two centimeters obtained. way, inter-module gate promising implemented performance comparable intra-module operations. Moreover, help through-silicon vias technologies, long-range also allow one implement couplers multi-chip stacked processor. Thus, longer-range proposed architecture provide foundation solving toward large-scale information processing