Chip-to-chip superconducting liquid metal quantum connectors

Combining different levels of quantum connectors to couple qubits across chips allows for scaling quantum systems at will. Among them, chip-scale short-range connectors effectively extend the size of quantum processors with minimal cost in gate speed and fidelity because they are short enough to function as single-mode connectors. Here, we present micro-scale, low-loss liquid metal droplets interconnecting two halves of coplanar waveguide resonators across chips. Leveraging the desirable fluidic properties of gallium alloys at room temperature, this approach adds flexibility in replacing defective modules.