Rigetti Computing (RGTI), IonQ (IONQ), and other quantum computing stocks fell more than 40% Wednesday after Nvidia (NVDA) CEO Jensen Huang told Wall Street analysts that “very useful quantum computers” are likely 20 years away.

Rigetti Computing dropped over 49%, and IonQ dropped 47%. Fellow stocks in the sector, D-Wave Quantum (QBTS) and Quantum Computing (QUBT), plummeted 48% and 50%, respectively.

Responding to a question from Evercore ISI analyst Mark Lipacis during a conversation with analysts at the tech industry’s annual CES trade show in Las Vegas, Huang said: “Quantum computing can't solve every problem.”

“If you kind of said 15 years for very useful quantum computers, that'd probably be on the early side. If you said 30 is probably on the late side. But if you picked 20, I think a whole bunch of us would believe it,” he said.

Quantum computing stocks enjoyed a massive rally in late November and throughout December as growing interest and technological advancements fueled bets that the technlogy will take off sooner rather than later.

In November, Amazon launched a quantum computing advisory program, saying in its announcement that the initiative will help AWS customers “get ready for quantum computing.” IonQ said on Nov. 18 that it had successfully run Nvidia’s quantum computing developer kit on its hardware. Quantum Computing Inc. said it had taken stock of advanced chips it’s using to advance its quantum software.

The US government gave a nod to the budding industry when a group of bipartisan US senators on Dec. 3 introduced a bill that would reauthorize the 2018 National Quantum Initiative Act and pledged an additional $2.7 billion for quantum computing research to develop practical applications. Then on Dec. 9, Google introduced a new quantum computing chip called Willow, and the company said it had found a way to increase the power of the chip while cutting down some of the problems associated with the technology (typically, the more powerful the quantum computer, the more prone it is to errors).

Even with their massive drops Wednesday, Quantum Computing is up nearly 1,400% from six months ago, while Rigetti has risen more than 850%, D-Wave has soared 360%, and IonQ has jumped 265% over that time frame.

Reuters / Reuters

Though Huang sees the tech taking longer to reach practical applicability, Nvidia is still betting on it. Huang said Nvidia is working with “just about every quantum computing company.” Nvidia in 2022 began extending its CUDA software development kit (currently used by developers to make artificial intelligence applications) for quantum software developers.

But Huang said the company will continue focusing on accelerated computing that complements quantum computing rather than diving head first into the space.

“[I]n the case of quantum computing, it turns out that you need a classical computer to do error correction with the quantum computer. And that classical computer better be the fastest computer that humanity can build, and that happens to be us,” Huang told analysts Tuesday. 

Laura Bratton is a reporter for Yahoo Finance. Follow her on Bluesky @laurabratton.bsky.social. Email her at laura.bratton@yahooinc.com.

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