Scientists have developed the most intense laser ever created. The beam of light delivers a whopping 10²³ W/cm², an intensity equivalent to concentrating the entire luminosity of the Sun into an area the size of a small office desk. And yes, the desk would be absolutely decimated under those conditions. 

The achievement, reported in the journal Optica, is more than a 10-fold improvement on the previous highest intensity achieved in 2004 at the University of Michigan. The creation of an ultra-intense laser beam requires two crucial things. You have to have a very powerful laser and you have to be able to focus it on a very small area. The team at the Center for Relativistic Laser Science (CoReLS) within the Institute for Basic Science (IBS) in South Korea managed to do both.

They used a pulsating laser with a power output of 4 petawatts (10¹⁵ or 1,000 trillion watts). This is among the most powerful in the world and researchers are already envisioning something 1,000 times more powerful.

Creating powerful lasers is a whole enterprise in itself but to concentrate the laser on a small area is an even bigger task. The laser beam needs to have no distortion at all because even a little bit can have a large effect. The team used an off-axis parabolic mirror to concentrate a 28-centimeter (11 inches) laser beam down to an area about 1.1 microns across. That area is smaller than the surface of a bacterium like E. coli.

Even with all the highly sophisticated setup the air turbulence and beam pointing were able to change the peak intensity by around 20 percent. That variation has an intensity over twice as strong as the University of Michigan's 2004 laser.

This achievement is not exciting only from a technical point of view. Creating such an intense laser can allow the investigation of extreme physical phenomena at the very edge of particle physics and astrophysics.

“This work has shown that the CoReLS PW laser is the most powerful laser in the world," Professor Nam Chang Hee, director of CoReLS said in a statement. "With the highest laser intensity achieved ever, we can tackle new challenging areas of experimental science, especially strong field quantum electrodynamics (QED) that has been dealt with mainly by theoreticians. We can explore new physical problems of electron-photon scattering (Compton scattering) and photon-photon scattering (Breit-Wheeler process) in the nonlinear regime. This kind of research is directly related to various astrophysical phenomena occurring in the universe and can help us to further expand our knowledge horizon.” 

 THIS WEEK IN IFLSCIENCE