Ina Vukic

2025 Nobel Prize in Physics

John Matthew Martinis of Croatian Roots

His father was a Croatian patriot from the island of Vis who fled Yugoslavia as a young man following the rise of communism there in the years after the Second World War; his mother was born in the United States of America and is said to also be of Croatian roots. Born and educated in the United States of America he is first generation American Croat – John Mattew Martinis, Professor of Physics at the University of California, Santa Barbara, who shared the 2025 Nobel Prize in Physics. As a pioneer in the development of quantum computing and a member of the Nobel Prize-winning team, he has been one of the most influential figures in the field of modern physics and, to boot, his paternal Croat ethnic roots, which escaped from communist Yugoslavia, appear quite similar to mine (and to multitudes I know living in the diaspora whose parent/s fled the oppression of communist Yugoslavia after Second World War and in 1950’s), which adds richly to my personal deep respect and pride for scientific achievers and trail blazers in the world, generally.

On 10th December 2025, in Stockholm, the Nobel Prize Awards ceremony was held. This year’s Nobel Prize laureates in Physics conducted experiments with an electrical circuit in which they demonstrated both quantum mechanical tunnelling and quantised energy levels in a system big enough to be held in the hand.

Quantum mechanics allows a particle to move straight through a barrier, using a process called tunnelling. As soon as large numbers of particles are involved, quantum mechanical effects usually become insignificant. The laureates’ experiments demonstrated that quantum mechanical properties can be made concrete on a macroscopic scale.

In 1984 and 1985, John Clarke, Michel Henri Devoret and John Matthew Martinis (2025 Nobel Prize winners for Physics) conducted a series of experiments with an electronic circuit built of superconductors, components that can conduct a current with no electrical resistance. In the circuit, the superconducting components were separated by a thin layer of non-conductive material, a setup known as a Josephson junction. By refining and measuring all the various properties of their circuit, they were able to control and explore the phenomena that arose when they passed a current through it. Together, the charged particles moving through the superconductor comprised a system that behaved as if they were a single particle that filled the entire circuit.

This macroscopic particle-like system is initially in a state in which current flows without any voltage. The system is trapped in this state, as if behind a barrier that it cannot cross. In the experiment the system shows its quantum character by managing to escape the zero-voltage state through tunnelling. The system’s changed state is detected through the appearance of a voltage.

The laureates could also demonstrate that the system behaves in the manner predicted by quantum mechanics – it is quantised, meaning that it only absorbs or emits specific amounts of energy.

“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,” says Olle Eriksson, Chair of the Nobel Committee for Physics. https://www.nobelprize.org/prizes/physics/2025/press-release/

This year’s Nobel Prize in Physics has provided opportunities for developing the next generation of quantum technology, including quantum cryptography, quantum computers, and quantum sensors.

“When I was a child, my parents didn’t ask me at the dinner table, ‘How was school?’ but rather, ‘Did you ask a question today?’ This is a great way to train a child to think scientifically, because our job as scientists is to ask questions,” says Professor John Matthew Martinis.

In an interview with Calcalist, Martinis explains that this is how he maintains his scientific curiosity, even after decades of practice. “Even questions that seem obvious can open the door to new nuances, sometimes in the answer and sometimes in the actual formulation of the question…I always learn something from the questions people ask, and from the way I am required to answer them. I just love being a scientist; it allows me to ask questions about the world every day. We need to encourage this in children too: to keep asking questions.”

When asked by Maayan Cohen-Rosen for Calcalist when it was that he realised that his experiments could become the basis for a real engineering platform John M. Martinis replied

“The moment I thought it was possible to build a quantum computer was in the first decade of the 2000s, when we started developing qubits. I’ve always been interested in building a quantum computer. In an experiment in 2008-2009, we were able to synthesize very complex photon states very precisely. For the first time, I realized that we could control these systems with great precision, and that maybe we could build a quantum computer from this. Then came the second big event, in 2019, after I joined Google, the quantum supremacy experiment. We showed that a quantum computer can be powerful. It’s not yet useful; it’s something that people are still working on, but we were able to show that you can do a powerful calculation for a mathematical problem. It changed the field a lot.”

Martinis believes that in five to ten years we could see quantum computers develop. “…We are all planning the infrastructure and technologies with such a timetable in mind, in order to be ready for the moment when it happens,” he said.

John Matthew Martinis now makes the fourth Nobel Prize winner of Croatian descent. Before him came:

Lavoslav (Leopold) Ruzicka (1887 – 1976), 1939 Nobel Prize in Chemistry.

Ivo Andric (1892 – 1975), 1961 Nobel Prize in Literature.

Vladimir Prelog (1906 – 1998), 1975 Nobel Prize in Chemistry.

An impressive outcome from a relatively small gene pool when comparing population numbers of countries in the world.

Hearty Congratulations to Professors John Matthew Martinis, John Clarke and Michel Henri Devoret! 

Ina Vukic and Croatian Film Institute