How Romania, one of the poorest countries in Europe, has the most powerful laser beam in the world

“Ready? Signal sent!” In the control room of a research center in Romania, Antonia Toma activates the most powerful laser beam in the world, which promises revolutionary milestones in medicine or space.

The system is capable of reaching a peak of 10 petawatts (a unit of power equivalent to one thousand billion watts) in an ultra-short time, on the order of a femtosecond (one billionth of a second).

In front of a wall of screens with light rays, the 29-year-old engineer and shooting director of the research center checks a series of indicators before starting the countdown.

The rate of shots fired against targets located in experimental chambers is currently very high: 30 to 40 shots per day.

A “stressful, but also very rewarding” job, given the research teams that come from all over the world to test this unique equipment, Toma explains to AFP during a press visit organized this week at these facilities on the outskirts of Bucharest.

Technological jewel

On the other side of the glass, long rows of red and black boxes house two laser chains.

Inside is a technological feat: titanium sapphire crystals that are activated by an optical pump to emit the laser beamhundreds of mirrors of all sizes, gold-coated diffraction gratings…

It took “several tens of millions of euros, 450 tons of material” and a meticulous installation to “achieve this exceptional level of performance,” details Franck Leibreich, head of laser activities for the French group Thales that operates the system.

This country, one of the poorest in the EU, proudly boasts of the building, equipped with anti-vibration walls, which required an investment of 320 million euros ($345 million) financed mainly by Brussels.

However, Construction of a gamma ray production unit ran into problems and will not be completed until 2026.

“A huge step”

Walking through the enormous room with an immaculate white floor, The 2018 Nobel Prize in Physics Gérard Mourou says he is “very excited” about the “incredible odyssey” of this project: It was conceived in the United States, where he lived for 30 years, and was implemented in Europe in the 2000s within the ELI (Extreme Light Infrastructure) program.

“We start from a small seed of light with very, very little energy, which will be amplified millions and millions of times”explains the French scientist who, despite his 79 years and gray hair, maintains the appearance of a child amazed at the “enormous step achieved” and the “phenomenal potentialities” expected.

This technique, called Twitter Pulse Amplification (CPA)developed it in the mid-1980s with Canadian researcher Donna Strickland, also awarded the Nobel Prize in Physics in 2018. It consists of extending the laser pulse, amplifying it and then compressing it.

In addition to contributing to the physics of the vacuum or black holes, the work of these two scientists has allowed millions of people suffering from myopia or cataracts to operate.

And the latest feats will allow us to go much further, especially in the medical field, says Professor Mourou.

“We are going to use these ultra-intense pulses to produce much more compact and less expensive particle accelerators” to destroy cancer cells, he says.

“Like soldiers”

It could also be applied to treat nuclear waste by reducing the duration of its radioactivity. or “clean the space” of the numerous debris of human activity, which “is equivalent to four Eiffel towers, about 28,000 tons.”

In this case, “The laser could be used to ablate this debris and produce a kind of rocket effect capable of removing it from orbit.”

The laser, whose basic principles were described in 1916 by Einstein, has made a place in everyday life, from CDs to barcode readers in supermarkets, and in industry for precision welding or cutting processes.

These rays are of a single color (red, green, blue, etc.) unlike the ordinary light that bathes us, which is made up of different colors. All light waves go in the same direction and form a narrow beam.

Photons are identical, “like soldiers in marching order, in contrast to marathon runners” that make up the light produced by a lamp, explains Gérard Mourou metaphorically.

If the 20th century marked the triumph of the electron, The 21st century will be that of the laser, he is convinced.

In fact, there are already other countries such as France, China or the United States on the way to manufacturing even more powerful lasers.