However, to detect the photons, cryogenic temperatures are still required, he says, at least today. The quantum computer itself doesn’t need to be cold, he says. “It’s just to get the answer out, it needs to be cold.”
In addition to keeping their qubits at near-absolute-zero temperatures, companies looking at non-photonic approaches to quantum computers are also working on improving error correction so that they can scale their quantum computers.
“We’d rather not do error correction.” says Sizer. “We’d rather use all the qubits for computing, instead of correcting what we should have gotten right the first time. We’re trying to make very robust systems so we can cascade information from one state to another and not flip.”
That doesn’t necessarily mean that photonic computers won’t need any error correcting codes, he adds. “Just not the massive ones needed in other approaches, and in a perfect world, we wouldn’t need any at all.”
Another benefit to the photonic approach to quantum computing is that the industry already knows how to work with photons. Our communication infrastructure uses photons – typically the regular kind, not the quantum entangled kind – but even entangled photons have been successfully sent over traditional fiber.
Plus, computer chips are already made with wave guides – metal or glass tubes that move photons around. Semiconductor manufacturers fabricate them right into wafers. These wave guides are used to enable faster data transfers inside and between computer components and are particularly useful for high performance computing and AI.
