The most infamous example of the lossy qubit problem surfaced in October
2019, when researchers at Google announced they had completed a benchmark
test on a 53-qubit quantum computer in 200 seconds. The test would have
taken a classical supercomputer far longer—anywhere from a few days to
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nicknamed Sycamore, Google claimed to have achieved quantum supremacy, or
proof that a quantum computer can handle an algorithm faster than a classical
computer can without making any mistakes. It’s something of a holy grail in the
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to hail it as quantum computing’s “hello world” moment.
Soon after, though, researchers disputed whether the experiment was as
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Oliver, a physicist at MIT who studies qubits, the larger problem with quantum
supremacy isn’t whether or not it exists, but when it breaks down.
“Most people in the world think [Google] achieved it,” he said of Sycamore. “But
had they added a couple more qubits, then they wouldn’t have been able to do
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supremacy over classical computers. The real holy grail, he says, is for quantum
computing “to be able to run anything for any amount of time without error.”
Even a year later, Jerry Chow still thinks of the Google announcement as a
footnote on the journey to create quantum computers that researchers and even
regular people can actually use without worrying about their accuracy or
stability. “That was an interesting academic work, to push that type of
problem,” Chow says of Sycamore.
Photo^ credit:^ Jon^ Simon/FeaturePhoto^ Service^ for^ IBMJerry Chow, IBM
researcher in the
Experimental
Quantum Computing
group, prepares for a
quantum experiment.