Superconducting Liquid Metal Interconnecting Quantum Computing

Abstract

Unlike reliable classical bits using transistors, superconducting qubits are vulnerable to fabrication defects and aging, necessitating their occasional replacement. A modular system allowing chip plug-and-play could tackle this challenge. Here, we propose liquid gallium alloys as interconnects between quantum computing chips, potentially enabling non-destructive replacement of these chips at room temperature after low-temperature benchmarking of the entire system. The comparable quality factors of conventional and liquid-metal-bridged coplanar waveguide resonators at millikelvin and single-photon regimes lay the foundation for leveraging such liquid metal interconnects in a modular quantum computer.