When the researchers used their system to measure the qubits’ state, they achieved an accuracy of 98 percent, exactly the same as when they carried out the measurement using a conventional electrical cable.

The authors acknowledge that work is already underway to try and reduce the heat produced by current approaches, including the development of thinner wires, proposals to replace wires with superconducting cables, or a process called multiplexing that makes it possible to send many signals over the same cable simultaneously.

But optical fiber is a well-established technology, and is already replacing electrical wires in many areas of computing thanks to its ability to carry far more data. The authors also point out that components used in this experiment were designed to work at room temperature, so optimizing them for cryogenic temperatures could provide significant performance gains.