That’s the thing. Or a lot of shielding but how many layers and of what materials and what would be acceptable loss?
I think having predictable “noise styles” based on shielding materials interactions to be subtracted out classically could help, but of course with each insertion of classical you lose a big chunk of benefit.
Still, not all.
I saw a fascinating circuit that handles spin state ‘reading / writing’ that’s in production now — a far cry from an all-quantum computing system but as it’s a combination logic / memory / long term storage circuit, it eliminates that separation at least.
Turn off computer, maintains state. It’ll be a huge leap forward and might possibly be a sturdier platform to work with qubits from. I dunno yet. [DARPA’s involved]