Science and Technology

Nobel Prize in Physics – a comment from a Técnico professor

The prize was awarded to scientists who developed experiments to detect the behaviour of electrons at the attosecond scale.

The winners of the Nobel Prize in Physics 2023 were announced this Tuesday: Anne L’Huillier, Ferenc Krausz and Pierre Agostini were awarded for their contributions to observing the behaviour of electrons using pulses of light at the attosecond scale (which corresponds to 0.00 000 000 000 000 000 1 seconds).

Reactions of several professors, researchers, and other members of Técnico community in several newspapers:

Marta Fajardo, a Técnico professor at the Department of Physics and a researcher at the Institute for Plasmas and Nuclear Fusion (IPFN), gives her perspective on the award.

We’re talking about a new method for studying the behaviour of electrons. What phenomena will we be able to observe more clearly?

This method has revolutionized the entire acquisition of ultrafast physical phenomena. As in the case of photography, if we want to photograph moving objects, we use a flash of light that illuminates the scene in an instant, during which everything appears motionless. We can now make images of any ultra-fast process in “slow motion”, because we can get illuminations that last only a few attoseconds. Before we could only see the before and after of any state, we can now see ultrafast transitions. The applications are countless, from Chemistry, Solid State Physics, Electronics…. For example, it was recently measured that the photoelectric effect lasts about 45 attoseconds.

Do you use this technology in your research work?

Yes, we’ve already been using this technology for several years, for example, to make images of dense plasmas, in the context of laser nuclear fusion. One of the things we don’t know is how quickly electrons heat up when a laser irradiates a solid, and how slowly they lose their energy to ions. In the VOXEL laboratory [which is part of IPFN] we have made videos of titanium plasmas going from the solid state to the plasma state. To do this, we used High Harmonics from an ultrafast laser, the ultrafast light source that won the Nobel Prize yesterday, to illuminate our plasma. We also play games with this light, such as controlling its spatial shape and even propagating it in the shape of a fusilli.

What areas will benefit from the development of this technology? What improvements and advances could come from it?

All ultrafast processes benefit from this technique. More advances will come when we master photonic computing, because the speeds of cycles per second that can be achieved with light are much higher than those of conventional electronics.

What other advances in the field of physics would you like to have seen awarded?

We can immediately think of the success of Nuclear Fusion with lasers, which demonstrated a gain in energy last year, and this year with an even greater gain.

Anne L’Huillier is the fifth woman to receive the Nobel Prize in Physics, out of 224 researchers who have won the prize since 1901. What do you think of the appreciation of the role of women scientists, particularly in recent years?

It’s very important that women receive the Nobel Prize, because it shows that physics is not a boys’ club, especially for young women who aspire to be scientists. Nobel prizes are often given for discoveries made quite some time ago, when there were practically no girls in research. Over time, inevitably many more women will be awarded.