Two Oddball Ideas for a Megaqubit Quantum Computer

The perpetual problem with scaling up most quantum computers is a seemingly mundane one—too many cables. Experts say quantum computers might need at least a million qubits kept at near absolute zero to do anything computationally noteworthy. But connecting them all by coaxial cable to control and readout electronics, which work at room temperature, would be impossible.

Computing giants such as IBM, Google, and Intel hope to solve that problem with cyrogenic silicon chips that can operate close to the qubits themselves. But researchers have recently put forward some more exotic solutions…