[DigitalToday reporter Jinju Hong (홍진주)] The race to invest in quantum computers is heating up further. The U.S. government and major big tech companies are accelerating development, presenting 2028 to 2030 as a turning point for practical use. Researchers, however, say commercially meaningful results have not yet been proven.

The Verge reported on June 30 (local time) that today’s quantum computers are not large enough and have high error rates, and there is still no confirmed case of solving problems at a level usable in industry. Quantum computers have the potential to carry out far more complex calculations than conventional computers. Researchers broadly agree they have yet to move beyond the laboratory stage.

Even so, the United States is stepping up efforts to foster the quantum industry. President Donald Trump’s science adviser recently set a goal of developing, by 2028, a quantum computer capable of being used for scientific research. Trump also signed an executive order to support the U.S. quantum computing industry with an eye on technology competition with China. The administration also announced a plan to shift government systems to post-quantum cryptography by 2030 to 2031.

Private companies are laying out similar blueprints. Microsoft unveiled a new quantum chip, Majorana 2, in June and said it had moved closer to building a scalable, practical quantum computer by 2029. IBM also set out a plan to invest more than $10 billion over the next 5 years to build a data-center-class quantum computer with 200 logical qubits by 2029. Quantinuum also set a goal of implementing several hundred logical qubits by 2030.

Researchers say a wide gap still remains between corporate blueprints and the actual technology. Henry Legg (헨리 레그), a physicist at the University of St Andrews in Britain, strongly criticised Microsoft’s announcement as "complete nonsense". In a paper recently published in the international journal Nature, he said there were significant differences among Microsoft’s research presented last year, its paper and its press release. He also said the Majorana particle cited as a core technology has not yet been sufficiently verified to exist, and that the publicly released data make it hard to support the company’s claims.

Microsoft immediately rebutted that criticism. Chetan Nayak (체탄 나약), head of quantum computing, said he had "100 percent confidence" in the company’s research results and roadmap, and argued the paper showed that Majorana particles were in fact created and controlled. Rajibul Islam (라지불 이슬람), a professor at the University of Waterloo, said, "At the current stage, it is hard to call this a technology."

The biggest barrier quantum computers must overcome is error. Qubits, the basic unit of quantum computers, are highly sensitive to external environments and cannot retain information for long, and errors accumulate quickly as calculations become longer. To address this, the industry is focusing on developing error correction technology that distributes a single piece of information across multiple physical qubits for storage.

The field has also seen what were described as meaningful advances recently. Google said in 2024 it implemented one logical qubit using 105 physical qubits. In 2025, IBM and Amazon said they reduced the number of physical qubits needed to implement one logical qubit to about 12 and 9, respectively, and Quantinuum claimed it lowered the number to 2. A Princeton University research team also said last November it developed a superconducting qubit with information retention time more than 3 times longer than before.

Some say progress in error correction does not mean practical use is immediately possible. Google said in 2019 it achieved so-called quantum supremacy, but the calculation it performed at the time was random number generation, far from real industrial applications. A molecular simulation it announced last year was also designed for research purposes, and was assessed as different from solving real industrial problems.

Dries Sels (드리스 셀스), a professor at Boston University, said, "Even if we received equipment with several hundred qubits capable of error correction right now, it is not clear what we could use it for."

The potential of quantum computers themselves remains valid. Researchers say that if molecular simulation capability is secured, quantum computers could outperform existing supercomputers in areas such as new drug development, next-generation batteries and solar cell design.

Eleanor Crane (엘리너 크레인), a professor at King's College London, said that if quantum phenomena in photosynthesis and solar cells can be precisely simulated, it would help both understanding natural phenomena and developing next-generation solar cells. She projected that some scientific research could see practical use around 2028.

Other experts are more cautious. Andrew Houck (앤드루 하우크), a professor at Princeton University, said it may be necessary to wait until at least 2035 for practical quantum computers to emerge. Islam also projected that large-scale applications at the level of cracking encryption would take at least 10 more years. Legg said, "There is still no definitive evidence that a useful quantum computer will be realised in the next 10 years, or perhaps even decades."

In this situation, the quantum industry appears to be seeing investment and roadmap competition heat up ahead of technology validation. The U.S. government and companies are presenting around 2028 to 2030 as a turning point for practical use, but for now the key questions remain whether errors can be reduced while scaling up, and what problems such equipment could actually solve.