Quantum Computing Wins Nobel Prize

Quantum Dawn: Nobel Prize Honours Pioneers Who Brought Bizarre Physics into the Real World

Three US-based scientists have been awarded the Nobel Prize for physics for foundational work that dragged the strange rules from the subatomic realm into our everyday experience. Michel H. Devoret, John M. Martinis, and John Clarke received the award for their research during the 1980s that established the foundation for today's powerful quantum computers. Their research demonstrated that the bizarre properties of the subatomic realm could be observed and controlled in specially designed electrical circuits, a discovery with profound implications for technology and science.

In Stockholm, the Royal Swedish Academy of Sciences made the announcement, highlighting the trio's achievement, which it described as discovering macroscopic quantum mechanical tunnelling and also energy quantisation within an electrical circuit. This work is now fundamental to the global race to build machines that could solve problems currently intractable for even the most powerful supercomputers. The laureates will share an award of 11 million in Swedish kronor, equivalent to £872,000.

From Cambridge to California: The Laureates' Journeys

The laureates represent a blend of European roots and American scientific enterprise. One recipient, Professor John Clarke, is from Cambridge in the UK, born in 1942, and has spent most of his career with the University of California's Berkeley campus. Educated at Cambridge University, he moved to Berkeley as a postdoctoral scholar in 1968 and joined the faculty a year later. His extensive research has focused on superconductivity and its applications.

French-born Michel H. Devoret holds a professorship at Yale University and also serves as the Chief Scientist of Quantum Hardware at Google. During the prize-winning research, he was a postdoctoral researcher in Clarke's Berkeley laboratory. John M. Martinis, who is now a professor with the University of California in Santa Barbara, was a graduate student under Clarke's supervision during that period. Their collaboration at Berkeley in the mid-1980s created the perfect environment for their breakthrough experiments.

The Science Behind the Prize: A Quantum Leap

The laureates' work confronted a central puzzle of physics. Quantum mechanics governs the universe at the scale of atoms and electrons, where particles can exist in multiple states at once (superposition) or pass through solid barriers in a phenomenon called "tunnelling". Classical physics, which governs our everyday world, does not allow for such counterintuitive behaviour. A ball, for instance, cannot pass through a wall.

Clarke, Devoret, and Martinis designed and built tiny electrical circuits which, when cooled to temperatures just above absolute zero, behaved like a single "macroscopic" quantum object. They observed currents tunnelling through an insulating barrier within the circuit, a feat impossible under classical rules. They also showed the circuit's energy levels were quantised, meaning they could only exist in specific, discrete amounts, much like the energy levels of an atom.

Unlocking a Strange New World

The concept of quantum tunnelling is deeply counterintuitive. It relies on the wave-particle duality of matter, where a particle like an electron also behaves as a wave of probability. This wave can extend through a barrier, meaning there is a non-zero chance of finding the particle on the other side, even if it lacks the energy to climb over it. This effect is crucial for phenomena like nuclear fusion in the sun.

The trio's experiments proved this was not just a feature of the microscopic world. By engineering superconducting circuits, they created a system large enough to be fabricated and controlled, yet which still obeyed quantum laws. This discovery was the essential first step towards building a quantum computer, as it provided a physical system—the basis for the "qubit"—that could be manipulated to store and process quantum information.

The Birth of the Superconducting Qubit

The electrical circuits pioneered by the Nobel laureates are the direct ancestors of today's leading quantum computing hardware: superconducting qubits. A qubit is the quantum equivalent of a classical computer bit. While a bit can be either a 0 or a 1, a qubit can be a 0, a 1, or both simultaneously, thanks to superposition. This property allows quantum computers to perform many calculations at once.

The laureates' research showed that Josephson junctions—tiny insulating gaps between two superconductors—could be used to create these qubits. Their ability to control and measure the quantum state of these circuits laid the experimental foundation for a new technological field. Many of today's most advanced quantum processors, including those developed by Google and IBM, use this fundamental architecture.

Laying the Groundwork for a Computing Revolution

The practical implications of the laureates' discovery are vast and still unfolding. Quantum computers promise to revolutionise fields as diverse as medicine, materials science, and finance. By simulating molecular interactions with perfect accuracy, they could accelerate the discovery of new drugs and the development of novel materials for things like more efficient batteries. Their ability to solve complex optimisation problems could transform logistics and financial modelling.

Professor Clarke, speaking by phone to reporters, noted that their work serves as the foundation in many respects for the ongoing development of quantum computers. He expressed his complete shock at receiving the award for research completed four decades ago, stating that when the research was conducted, they had no idea of its Nobel-worthy potential. His sentiment underscores how fundamental research can often take decades to be fully appreciated.

The UK's Stake in the Quantum Future

The United Kingdom has positioned itself as a key player within the field of quantum technology. Recognising the field's transformative potential, the government has made substantial investments through the National Quantum Technologies Programme, which began in 2014. The strategy aims to translate academic research into commercial applications, driving economic growth and enhancing national security.

Recent government announcements have pledged hundreds of millions of pounds to bolster this effort. In April 2025, a £121 million investment was detailed to support various quantum initiatives, including the National Quantum Computing Centre at Harwell. This funding aims to accelerate the deployment of quantum technologies in sectors like finance and healthcare and to train the next generation of quantum scientists and engineers. A further commitment in June 2025 promised over £500 million over four years to secure national leadership in the field.

Global Competition and Collaboration

The race to build a useful quantum computer is a global one. Nations and technology companies are investing billions, driven by the promise of economic advantage and national security. The United States has pursued an aggressive strategy through its National Quantum Initiative Act, first passed in 2018. This act coordinates efforts across government agencies, industry, and academia to accelerate research and development.

This initiative has been reauthorised and expanded, reflecting the escalating importance of the field. A recent bipartisan bill proposed authorising a further $2.7 billion over five years to shift the focus from basic research towards developing practical applications. China, meanwhile, has declared its ambition to surpass the US in quantum technology, pouring vast resources into research facilities. This international competition is a powerful driver of innovation.

The Challenges of Building a Quantum Computer

Despite enormous progress, constructing a large-scale, fault-tolerant quantum computer remains a monumental engineering challenge. Qubits are incredibly fragile and sensitive to their environment. The slightest vibration or change in temperature can cause them to lose their quantum state in a process called decoherence, which corrupts calculations. This fragility is a major hurdle to scaling up quantum processors.

Managing and correcting errors is another critical issue. Current quantum systems are "noisy," meaning errors accumulate rapidly. Scientists are developing complex quantum error correction codes, but these require a huge overhead of physical qubits for each single reliable "logical" qubit. Furthermore, the hardware needed to control and cool superconducting qubits to near absolute zero is complex and expensive, posing further scaling difficulties.

Quantum's Double-Edged Sword for Cybersecurity

Among the most discussed applications of quantum computing is its ability to break modern cryptography. Many of the encryption standards that protect everything from online banking to government secrets rely on the difficulty of factoring large numbers. A sufficiently powerful quantum computer running Shor's algorithm could solve these problems with ease, rendering much of our current digital security obsolete.

This has created a new cybersecurity imperative. Experts are developing "quantum-resistant" or "post-quantum" cryptographic algorithms that are secure against attacks from both classical and quantum computers. At the same time, quantum mechanics itself offers a solution in the form of Quantum Key Distribution (QKD), which uses the principles of quantum physics to create theoretically unhackable communication channels. The transition to these new security standards is a pressing global challenge.

The Ethical Landscape of Quantum Technology

As with any transformative technology, the rise of quantum computing brings with it a host of ethical considerations. The immense power of these machines raises questions about who will control them and how they will be used. There are concerns that quantum computing could exacerbate existing inequalities, as the resources to develop and access this technology are likely to be concentrated in the hands of a few wealthy nations and corporations.

Furthermore, the potential for mass surveillance and the disruption of global security through codebreaking demands careful governance. Organisations like the World Economic Forum have begun to establish ethical frameworks to guide the responsible development and deployment of quantum technologies. Ensuring transparency, accountability, and equitable access will be crucial to harnessing quantum computing for the benefit of all humanity.

Beyond Computing: A New Wave of Technology

The impact of the laureates' work extends far beyond computing. The ability to manipulate macroscopic quantum systems has opened the door to a fresh wave of ultra-precise sensors and secure communication networks. Quantum sensors could have applications in medical diagnostics, allowing for earlier detection of diseases, and in navigation systems that function independently of satellites.

The committee behind the Nobel Prize explicitly recognised that the trio's research is helping to develop this next wave of quantum technology. Dr Mark Mitchison, a quantum expert at King's College London, noted that many modern developments are built directly upon their discoveries. The prize is a celebration of fundamental research that has unlocked an entirely new technological paradigm, one whose full potential is only just beginning to be realised.

Looking to the Future: An Unwritten Chapter

The journey from the experiments in a Berkeley lab during the 1980s to the quantum technologies of today has been remarkable. The 2025 Nobel Prize for physics honours the vision and ingenuity of three scientists who dared to explore the boundary between the quantum and classical worlds. Their work did not just confirm a strange prediction of quantum theory; it provided the tools to harness that strangeness.

While the path to a universal quantum computer is still fraught with challenges, the foundations they laid are secure. The coming decades promise to be an exciting era of discovery, with quantum technology poised to reshape our world in ways we can now only begin to imagine. The work of Michel H. Devoret, John M. Martinis, and John Clarke will forever be recognised as the critical starting point of this new technological age.