https://www.wired.com/story/microsoft-win-quantum-computing-error/In March 2018, Dutch physicist and Microsoft employee Leo Kouwenhoven publis
hed headline-grabbing new evidence that he had observed an elusive particle
called a Majorana fermion.
Microsoft hoped to harness Majorana particles to build a quantum computer, w
hich promises unprecedented power by tapping quirky physics. Rivals IBM and
Google had already built impressive prototypes using more established techno
logy. Kouwenhoven’s discovery buoyed Microsoft’s chance to catch up. The c
ompany’s director of quantum computing business development, Julie Love, to
ld the BBC that Microsoft would have a commercial quantum computer “within
five years.”
Three years later, Microsoft’s 2018 physics fillip has fizzled. Late last m
onth, Kouwenhoven and his 21 coauthors released a new paper including more d
ata from their experiments. It concludes that they did not find the prized p
article after all. An attached note from the authors said the original paper
, in the prestigious journal Nature, would be retracted, citing “technical
errors.”
Two physicists in the field say extra data Kouwenhoven’s group provided the
m after they questioned the 2018 results shows the team had originally exclu
ded data points that undermined its news-making claims. “I don’t know for
sure what was in their heads,” says Sergey Frolov, a professor at the Unive
rsity of Pittsburgh, “but they skipped some data that contradicts directly
what was in the paper. From the fuller data, there’s no doubt that there’s
no Majorana.”
The 2018 paper claimed to show firmer evidence for Majorana particles than a
2012 study with more ambiguous results that nevertheless won fame for Kouwe
nhoven and his lab at Delft Technical University. That project was partly fu
nded by Microsoft, and the company hired Kouwenhoven to work on Majoranas in
2016.
The 2018 paper reported seeing telltale signatures of the Majorana particles
, termed “zero-bias peaks,” in electric current passing through a tiny, su
percold wire of semiconductor. One chart in the paper showed dots tracing a
plateau at exactly the electrical conductance value that theory predicted.
Frolov says he saw multiple problems in the unpublished data, including data
points that strayed from the line but were omitted from the published paper
. If included, those data points suggested Majorana particles could not be p
resent. Observations flagged by Frolov are visible in the charts in the new
paper released last month, but the text does not explain why they were previ
ously excluded. It acknowledges that trying to experimentally validate speci
fic theoretical predictions “has the potential to lead to confirmation bias
and effectively yield false-positive evidence.”
Microsoft provided a statement attributed to Kouwenhoven saying he could not comment, because the new paper that reinterprets his group’s results is undergoing peer review. “We are confident that scaled quantum computing will help solve some of humanity’s greatest challenges, and we remain committed to our investments in quantum computing,” he said. Nature added an “editorial expression of concern” to the 2018 paper in April last year, and a spokesperson said this week that the journal is “working with the authors to resolve the matter.” A spokesperson for Delft Technical University said an investigation by its research integrity committee, started in May 2020, is not complete. A person familiar with the process says the final report will likely find that researchers at Delft made mistakes but did not intend to mislead.
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