In a paper that made the cover of the journal Applied Physics Letters, a world team of researchers has demonstrated an innovative technique for growing the intensity of lasers. This strategy, based mostly on the compression of gentle pulses, would make it potential to attain a threshold intensity for a new kind of physics that has never been explored earlier than quantum electrodynamics phenomena.
Researchers Jean-Claude Kieffer of the Institut national de la recherche Scientifique (INRS), E. A. Khazanov of the Institute of Applied Physics of the Russian Academy of Sciences and in France Gérard Mourou, Professor Emeritus of the Ecole Polytechnique, who was awarded the Nobel Prize in Physics in 2018, have chosen one other route to achieve a power of around 1023 watts (W). Rather than increasing the energy of the laser, they decrease the pulse duration to only a few femtoseconds. This would keep the system within a cheap measurement and hold operating costs down.
To generate the shortest possible pulse, the researchers are exploiting the effects of non-linear optics. “A laser beam is distributed by a particularly skinny and perfectly homogeneous glass plate. The explicit behaviour of the wave inside this strong medium broadens the spectrum and permits for a shorter pulse when it’s recompressed on the exit of the plate,” explains Jean-Claude Kieffer, co-author of the study published online on June 15, 2020, in the journal Applied Physics Letters.
If we achieve very short pulses, we enter relativistic drawback classes. This is an extremely fascinating route that has the potential to take the scientific community to new horizons,” says Professor Kieffer. “It was a very good piece of work solidifying the paramount potential of this technique,” concludes Gérard Mourou.
They have received monetary help from the Natural Sciences and Engineering Research Council of Canada, the Canada Foundation for Innovation, the ministère de l’Économie, de la Science et de l’Innovation du Québec and the Ministry of Science and Higher Education of the Russian Federation.