The 2025 Nobel Prize in Physics has been awarded to John Clarke, Michel H. Devoret, and John M. Martinis for their landmark discovery of macroscopic quantum mechanical tunnelling and energy quantisation in an electric circuit, an innovation that laid the foundation for today’s quantum computing revolution.

Announcing the prize, Olle Eriksson, Chair of the Nobel Committee for Physics, said, “It is wonderful to be able to celebrate the way that century-old quantum mechanics continually offers new surprises. It is also enormously useful, as quantum mechanics is the foundation of all digital technology.”

The Committee described their discovery as a “turning point in understanding how quantum mechanics manifests at the macroscopic scale,” bridging the gap between classical electronics and quantum physics.

John Clarke: The SQUID Pioneer

British-born John Clarke, Professor Emeritus at the University of California, Berkeley, is celebrated for his pioneering work on Superconducting Quantum Interference Devices (SQUIDs) — ultra-sensitive detectors of magnetic flux. His career has been marked by contributions that span superconductivity, quantum amplifiers, and precision measurements.

Clarke’s experiments in the early 1980s provided the first clear evidence of quantum behaviour in electrical circuits — showing that entire electrical systems, not just atoms or photons, can obey the strange laws of quantum mechanics.

A Fellow of the Royal Society, Clarke has been honoured with numerous awards including the Comstock Prize (1999) and the Hughes Medal (2004).

Michel H. Devoret: Architect of Quantum Circuits

French physicist Michel H. Devoret, now the Frederick W. Beinecke Professor Emeritus of Applied Physics at Yale University, has been one of the intellectual architects of quantronics — the study of quantum phenomena in electrical circuits.

After earning his PhD at the University of Paris-Sud and completing a postdoctoral fellowship under Clarke at Berkeley, Devoret helped establish the field of circuit quantum electrodynamics (cQED), which underpins the design of modern superconducting qubits.

His group’s innovations — from the single-electron pump to the fluxonium qubit — have set performance benchmarks in quantum coherence and control. Devoret is also a recipient of the Fritz London Memorial Prize (2014) and the John Stewart Bell Prize, and is a member of the French Academy of Sciences.

John M. Martinis: Building the Quantum Processor

American physicist John M. Martinis, who completed his PhD at UC Berkeley under Clarke’s supervision, translated these quantum principles into the hardware era. His experiments demonstrated energy level quantisation in Josephson junctions, one of the key results now honoured by the Nobel Committee.

Martinis later led Google’s Quantum AI lab, where his team in 2019 achieved the world’s first demonstration of quantum supremacy — showing a superconducting processor outperforming the fastest classical supercomputer on a specific task.

A former professor at UC Santa Barbara, Martinis continues to be a leading voice in quantum computing research and technology development.

A Legacy of Quantum Insight

Together, the trio’s discovery, once seen as a niche curiosity in superconducting circuits, has become the cornerstone of the global quantum revolution. Their experiments proved that macroscopic electrical systems can display quantised energy states and tunnel between them, much like subatomic particles.

Their work, as the Nobel citation puts it, “opened a new window into the quantum behaviour of engineered systems, enabling technologies that are redefining computation, communication, and sensing.”

For decades, silicon has been the undisputed workhorse in transistors—the microscopic switches responsible for processing information in every phone, computer, and high-tech device. But silicon’s physical limits have long frustrated scientists seeking ever-smaller, more efficient electronics.

Now, MIT researchers have unveiled a major advance: they’ve replaced silicon with a magnetic semiconductor, introducing magnetism into transistors in a way that promises tighter, smarter, and more energy-saving circuits. This new ingredient, chromium sulfur bromide, makes it possible to control electricity flow with far greater efficiency and could even allow each transistor to “remember” information, simplifying circuit design for future chips.

“This lack of contamination enables their device to outperform existing magnetic transistors. Most others can only create a weak magnetic effect, changing the flow of current by a few percent or less. Their new transistor can switch or amplify the electric current by a factor of 10,” the MIT team said in a media statement. Their work, detailed in Physical Review Letters, outlines how this material’s stability and clean switching between magnetic states unlocks a new degree of control.

Chung-Tao Chou, MIT graduate student and co-lead author, explains in a media statement, “People have known about magnets for thousands of years, but there are very limited ways to incorporate magnetism into electronics. We have shown a new way to efficiently utilize magnetism that opens up a lot of possibilities for future applications and research.”

The device’s game-changing aspect is its ability to combine the roles of memory cell and transistor, allowing electronics to read and store information faster and more reliably. “Now, not only are transistors turning on and off, they are also remembering information. And because we can switch the transistor with greater magnitude, the signal is much stronger so we can read out the information faster, and in a much more reliable way,” said Luqiao Liu, MIT associate professor, in a media statement.

Moving forward, the team is looking to scale up their clean manufacturing process, hoping to create arrays of these magnetic transistors for broader commercial and scientific use. If successful, the innovation could usher in a new era of spintronic devices, where magnetism becomes as central to electronics as silicon is today.

A path-breaking study from MIT offers a novel explanation for the most energetic neutrino ever detected: the final explosion of a primordial black hole (PBH). This research, published in Physical Review Letters, presents a compelling theoretical model suggesting that an ancient, microscopic black hole vaporizing just outside our solar system might be the source of this elusive “ghost particle.”

Neutrinos are known for their ghost-like ability to traverse space virtually undisturbed, making them difficult to detect despite being the universe’s most abundant particles. The recently observed neutrino, captured by the Cubic Kilometer Neutrino Telescope (KM3NeT) under the Mediterranean Sea, contained energy levels exceeding anything produced by human-made accelerators.

The MIT team, including lead author Alexandra Klipfel, explains that primordial black holes—hypothetical remnants from the early universe—slowly lose mass through Hawking radiation, emitting an array of particles as they evaporate. This process intensifies as the PBH shrinks, culminating in a violent final burst of energy. “It’s something we can now try to look for and confirm with various experiments,” Klipfel said in a media statement.

Co-author David Kaiser described the challenge: “We don’t have hope of detecting Hawking radiation from stellar black holes, so our best chance lies with tiny primordial black holes.” Their calculations estimate that thousands of such PBHs might explode yearly within the Milky Way, and there’s a roughly 8% chance one occurred close enough to Earth to explain the detected neutrino.

This discovery could represent the first observation of Hawking radiation and provide crucial insights into the mysterious dark matter that comprises 85% of the universe’s matter. However, confirming the theory requires more detections of these high-energy neutrinos.

Kaiser expressed cautious optimism: “If proven, it would validate pivotal aspects of black hole physics and unravel clues about dark matter’s nature.”

Ongoing and future experiments, like those tracking particle remnants from potential PBH explosions, offer hope in this cosmic detective story.