Microsoft Qubits Questioned Again

Microsoft has been trying to build quantum computers with topological qubits, which would have durability advantages if they worked. But SciAm reports:

A top quantum computing expert assails Microsoft’s claims that it has a “topological qubit,” arguing in a new paper that the company has failed to demonstrate the technology.

University of St Andrews physicist Henry Legg argues that the “topological qubit,” a storer of quantum information that could theoretically maintain a higher fidelity than any in existence, might simply be noise.

The commentary was published today in Nature’s “Matters Arising,” the journal’s venue for formal criticism of its published papers. Legg’s response is aimed at Microsoft’s most recent Nature paper, which was published earlier this month—but it is just the latest in a string of criticism aimed at Microsoft’s Quantum division by other researchers in the field.

The company has been forced to retract certain previous peer-reviewed papers. And in the new commentary, Legg argues that their most recent Nature paper may be similarly flawed. In a response also published today by Nature, a member of Microsoft’s Quantum team argues that their measurements do justify the claim that they’ve produced a topological qubit.

The Microsoft paper has about 150 authors. I did not understand it. Maybe Microsoft has done some Nobel Prize quality research, but I doubt it. I wonder how the scientists convince Microsoft management to keep funding it. There is no possibility of a monetary payoff.

I did not know that Nature had a journal for formal criticism of its papers. That seems like a good idea.