Quantum computing with superconductors

[annaphys]

I have some questions to this Ansatz and I would really appreciate it if I can get some insight:

1. What is the current status of gate fidelity and what are the current struggles to improve it?
2. Same question but with coherence times.
3. What are the current issues with scalability?
4. Could qc with superconductors be the wrong approach?
5. Is there anything else that the current research is focusing on?

 

[anuttarasammyak]

All these things are in progress. To know the current status you have some opportunities of free virtual conferences as an example https://quantum-innovation.riken.jp/.

 

[f95toli]

You should be able to find some current numbers just by Googling. For the rest of the questions I would suggest reading a recent review
E.,g.
https://www.nature.com/articles/s41578-021-00370-4
(I believe there is a free preprint version available if you don't have access)

Note that all numbers need some context. It is much easier to achieve good numbers for both coherence and fidelity in small circuits (2-qubits) where there are fewer challenges when it comes to fabrication, control and you don't have to worry about e.g. crosstalk
Also, coherence times for SC qubits fluctuate over time (by sometimes as much as 2-3 times). meaning a single number doesn't necessarily tell you very much about how well a circuit would run