Briefs · Frontier Science
Quantum tunnelling, now big enough to hold in your hand
Quantum mechanics is supposed to be small. The 2025 physics Nobel proves it can be the size of a circuit board.
On 7 October, the Royal Swedish Academy of Sciences awarded the Prize in Physics to John Clarke, Michel H. Devoret and John M. Martinis, “for the discovery of macroscopic quantum mechanical tunnelling and energy quantisation in an electric circuit”. In 1984 and 1985, at the University of California, Berkeley, the three ran experiments on a superconducting circuit — a system big enough to be held in the hand — and showed both quantum tunnelling and quantised energy levels in it.
Tunnelling is the trick by which a particle moves straight through a barrier it has no right to cross. The laureates showed that whole groups of particles, acting as one, can do the same. The current kept a recognisable identity as a single quantum entity throughout, and could only absorb or release energy in specific, quantised amounts.
This is not a curiosity, but rather the foundation of the modern world: superconducting qubits, the heart of many of today’s quantum computers, and the ultra-sensitive measurements inside MRI machines, all trace back to this work.
Conclusion: quantum physics is not microscopic, but rather macroscopic — palm-sized physics, with a Nobel to prove it.
Read the original at NobelPrize.org
Summary in our own words. The original belongs to its publisher.