2023 Nobel Prize winners in Physics announced

The Nobel Prize in Physics for 2023 has been awarded to three researchers for their work in developing experiments to measure events happening on the very shortest of timescales.

Anne L’Huillier, Pierre Agostini and Ferenc Krausz have been awarded the medal for their independent work on experiments that enable us to see processes happening within atoms and molecules. Their research field, known as attosecond physics, refers to the timescale of light pulses they have produced: an attosecond. This is such a small time interval that there are as many in one second as there have been seconds since the birth of the universe. 

The researchers’ contributions “open[ed] the door to the world of electrons”, enabling physicists to understand processes governed by the movement and interaction of electrons. “The next step,” says the Chair of the Nobel Committee for Physics, Eva Olson, “will be utilising them”. 

L’Huillier’s experiment is the earliest of the three, with the Laureate’s 1987 observations upon transmitting laser light through noble gases providing rich groundwork for future breakthroughs. L’Huillier, of Lund University, Sweden, discovered that many different overtones of light arose from this laser transmission,  from interactions between the laser light and the atoms in the gas. Electrons gain extra energy upon being hit with the laser light, which is then re-emitted as light at a wavelength related to the characteristics of the atom. For this reason, attosecond processes are useful in the identification of atoms and molecules, which has direct applications in the field of medicine. 

Agostini and Krausz worked independently in 2001 on these attosecond light pulses, at the USA’s Ohio State University and the Max Planck Institute of Quantum Optics, Germany respectively. Agostini produced and investigated a series of consecutive pulses, whilst Krausz developed an experiment that isolated a single pulse of slightly longer duration. Both methods were instrumental in developing ways to investigate electron dynamics in matter, which happen so fast that they were previously impossible to follow. 

Indeed, it was a long road to this breakthrough, with 1999’s Nobel Prize in Chemistry being awarded to Ahmed Zewail for studies on chemical transition states in reactions. This was made possible by developments in laser technology, which Agostini and Krausz built upon. 

The Laureates will travel to Sweden in December to formally receive their medal alongside winners in the categories of Physiology and Medicine, Chemistry and Economics, Literature and Peace.

Featured image credit: Johan Jarnestad/The Royal Swedish Academy of Sciences

Featured image description: A sketch of the Nobel Laureates, Pierre Agostini, Anne L’Huillier and Ferenc Krausz.