If Google Has Achieved ‘Quantum Supremacy,’ What’s Next for Its Competitors?

Google’s quantum computing competitors—including IBM, Intel, and Microsoft—say they’re not surprised by their rival’s apparent achievement of “quantum supremacy,” a demonstration that a quantum computer can perform a task infeasible for a traditional computer.

Google’s milestone made waves after a research paper describing the potentially historic result leaked on the website of NASA, a Google partner, as first reported by the Financial Times. The feat, now under scientific peer review, has never been achieved before.

Google’s nearest peer, IBM, which has taken a similar approach to quantum hardware (with so-called superconducting qubits, or “quantum bits”), has tamped down on the enthusiasm for its rival’s result. Other companies such as Intel, Microsoft, and Honeywell, have lauded the science, while recommitting to their own distinct approaches for designing quantum hardware.

Fortune gathered the reactions of the world’s leading quantum computing companies in the wake of Google’s result.

The superconductors

IBM has generally cautioned against overhyping the significance of demonstrating quantum supremacy. Dario Gil, head of IBM Research, has said that Google’s result represents a “laboratory experiment” with “no practical applications.”

Instead of designing specialized, one-off spectacles, IBM says it is focused on building “scalable” machines for broad scientific and commercial use. “The task ahead is to continue to build and make widely accessible truly programmable quantum computing systems,” Gil said.

Gil said his team is focused on creating machines that “reproducibly and reliably” run all variety of quantum software, rather than single algorithms for very specific demonstrations. The company just opened a quantum computation center in Poughkeepsie, N.Y., and it plans next month to install on-site a quantum computer bearing 53 qubits, the same number that Google put to use in its experiment.

Chad Rigetti, a former IBMer who runs Rigetti, a self-named Silicon Valley quantum computing startup that, like Google and IBM, also uses the superconducting qubit approach, alternatively heaped praise on Google’s work. “They’ve blazed a trail here,” Rigetti said. “It paves the way for others to reproduce these results going forward—ourselves included.”

Google “put all the pieces together with that level of fidelity for the first time is extremely important and I expect other demonstrations to follow in the next 12 months,” he added.

The other challengers

While Google’s experiment earns major plaudits for its chosen technology—superconducting qubits, the front-running approach—rivals such as Microsoft, Intel, and Honeywell believe their own competing methods hold just as much promise, if not more.

Krysta Svore, Microsoft’s general manger of quantum software, described Google’s result as “an exciting academic achievement.” She added that is does not represent the end of the line, but rather “another step on a long journey.”

Microsoft is betting on so-called topological qubits, a more theoretical approach to quantum hardware than Google and IBM’s. Topological qubits, which use strange, braided physics particles, are the qubit approach that is furthest behind, but they may ultimately offer the most stability.

“We continue to believe in order to scale you will need a revolutionary approach,” Svore told Fortune, pointing to the company’s unusual venture.

Tony Uttley, president of the quantum division at Honeywell, the industrial behemoth, is taking a different tack. His team is building on “trapped ion” qubits, which involve Ytterbium atoms suspended in a vacuum—a computer set-up that ideally yields lower error rates than superconducting qubits.

Uttley said Google’s milestone is “good for the industry in general” as it helps communicate how the world is entering the era of the “classically impractical.” In that era, quantum hardware will offer performance advantages over classical devices in terms of time and money for certain algorithms, he said.

Uttley said Honeywell is preparing to make announcements about its technology in the spring.

Jim Clarke, director of quantum hardware at Intel, views the Google result as a “positive.” Like his peers, he said he is “impressed” but that we’re “still early in the race.”

Intel is taking yet another approach to the creation of qubits—the “spin state” qubit. This flavor of quantum hardware is a relative of the classical transistor, an essential ingredient for semiconductors and Intel’s bread and butter.

Google’s “intermediary milestone” doesn’t change Intel’s strategy, Clarke said. While Intel is exploring superconducting qubits, the company is betting more on spin-state ones, though Clarke concedes they are “a little further behind from a technical perspective.”

But Clarke believes the technology “will accelerate in a relatively short amount of time, to surpass the capabilities of superconducting qubits.”

Google’s experiment is a good one, Clarke said. “It will motivate us.”