[mmmBacon]

Quantum computing is still a technology of the future. When we are still talking about 12 qubits as a breakthrough, there’s a long way to go. Optical interconnects are the least of quantum computing’s problems.

However, it’s not correct to say lasers are unreliable. It’s fundamentally false and it’s not supported by field data from today’s pluggable modules. 10’s of millions of lasers are deployed in data centers today in pluggable modules.

It’s also useful to remember that an LED is essentially the gain region of a laser without the reflectors. When lasers fail in the field, they fail for the same reasons an LED will fail; moisture or contamination penetration of the semiconductor material.

An LED is not useful for quantum computing. To create a Bell pair (2qubits) you need a coherent light source to create correlated photons. The photons produced by an incoherent light source like an LED are fundamentally uncorrelated.

[ziofill]

Actually optical interconnects are the biggest of (photonic) quantum computing problems. If we had good enough optical interconnects (i.e. with low enough optical loss) we would already have a fault-tolerant quantum computer. See https://www.nature.com/articles/s41586-024-08406-9 (also note that Aurora produces 12 physical qubit modes at each clock cycle)