IonQ (IONQ 5.27%), a very hot stock during the quantum computing bull run late last year and early in 2025, cooled down considerably on Thursday. Investors eagerly traded out of the stock on news from a monster rival in the tech sector, leaving IonQ with a more than 9% loss in price on the day. That was a far more dramatic tumble than the S&P 500 index's 0.2% slide.

A monster tech company plans to step into the quantum space

That heat was generated by another company that's seen fits of wild popularity lately, graphics hardware king Nvidia (NVDA -0.75%). As part of its annual software-developer conference this year, Nvidia devoted a day to the technology and business of quantum computing.

What surely worried IonQ investors and observers the most was the announcement by Nvidia CEO Jensen Huang that his company would open a quantum computing research laboratory. The facility is to be located in Boston, all the better to engage in cooperation with scientists from nearby Harvard University and the Massachusetts Institute of Technology.

That move represents quite the shift in attitude from Huang. This past January he said that practical and useful quantum computers are 20 years away from hitting the market. During a panel discussion with business people in the quantum space within the conference, he essentially admitted that he was mistaken.

Competitive advantages

The obvious implication from Nvidia establishing such a lab is that the company will siphon its knowledge and findings into its own potential quantum computing products. This would be a natural outgrowth of its business and strengthen its position as a leading company in the cutting-edge hardware space.

IonQ is, of course, much further along in quantum computing development, but it's a minnow compared to the whale that is Nvidia. Although it's rank speculation to consider how much of a threat the not-yet-existing Nvidia lab is going to be, it's entirely conceivable it'll have a potentially very negative effect on the business of quantum specialists like IonQ.