In fields such as computing, information security and precise measurement, quantum systems promise to outperform classical ones. And there’s been much progress over the century since the formulation of quantum mechanics.
Quantum computers have reached the ‘quantum advantage’ milestone: they are able to solve problems that classical supercomputers cannot. And one method of secure communication, quantum cryptography, uses keys that are known only to the parties involved — a form of unconditional security, which means the protection cannot be broken even with unlimited computer power.
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Quantum sensors are measuring both time and gravity with unprecedented precision. For instance, gravimeters for detecting earthquakes and for navigation are already commercially available.
However, other than these encryption devices and quantum sensors, few quantum technologies have practical applications. In the next few years, quantum simulations will probably advance fields such as quantum chemistry and high-temperature superconductivity. The community is making progress, but the development of noise-resilient quantum computers that can be used for a wide range of problems will take another 10–15 years. Current challenges include protecting the fragile states of quantum bits (qubits) from errors and unwanted interference from the environment.
Three steps would help to spur the field.
First, calm down the quantum-computing hype. As a quantum physicist with more than 30 years of experience, I’ve seen how oversold promises have attracted a lot of capital and attention but can lead to unrealistic expectations. Some companies suggest that they can provide quantum-computing services, for example, when they have merely demonstrated small-scale quantum algorithms.
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Exaggerated claims can mislead the public and investors and undermine societal confidence in quantum information technology. For example, January saw a collective plunge in quantum-computing stocks, triggering concerns that this technology bubble has now burst.
To prevent such stock-market jitters, academic and industrial research communities, as well as the media, must accurately communicate the state of quantum technology to the public, to foster realistic expectations.
Second, stable and long-term government investment is essential for the continued advancement of quantum information technology. Unlike mature technologies, such as the Internet or mobile phones, quantum information research cannot yet rely fully on market-driven financing.
Governments in the United States, Europe and China have increased their investments in quantum information research and development over the past few years. For example, the US National Quantum Initiative invested US$3.75 billion in 2023 — nearly triple its five-year budget of $1.3 billion (see go.nature.com/3cw6qtr). The next budget is in the process of being reauthorized, with a plan to allocate $2.7 billion over five years. But the eventual investment might be higher.