Absolutely loving this thread so far-these deep dives into the nitty-gritty technical hurdles make my day!
One super exciting area that hasn’t come up much yet is the emergence of modularity as a potential solution to some scaling roadblocks, especially for trapped ions. There’s a lot of recent buzz around photonic interconnects coupling separate ion traps. The networking approach sidesteps some wiring/laser complexity and paves a way to larger, distributed processors (like work by Monroe’s group and Honeywell/Quantinuum).
For superconducting qubits, I’m fascinated by the ongoing research into 3D integration (like “flip-chip” techniques and bump bonding). Companies like IBM and Google are demonstrating chip-stack architectures that could help with fanout and crosstalk. Still, the cryogenic wiring challenge is epic-hundreds of coax cables don’t scale well!
On hybrid approaches, there are real efforts in integrating the two: eg, superconducting qubits interfaced with trapped-ion memory nodes via photonics. Even connecting microwave and optical photons for cross-platform networking is being explored (check out Kimble’s 2008 Nature paper for theory, and some recent Nature comms about “quantum transducers”).
Would love to hear if anyone’s seen firsthand demos of error correction across these modules? Not just running surface code inside, but using modules as logical qubits. That’s a leap toward the modular, fault-tolerant era!