Scientists Create Bullets of Light
19 December 2013
Greek and French scientists have teamed up to demonstrate how a new type of light beam can focus itself into intense light bullets as it travels over extended distances, unlike other shapes of light that disperse over distances.
Controlling the spread of high-intensity light beams as they travel through air is not an easy task, but the researchers, P. Panagiotopoulos, D.G. Papazoglou, A. Couairon and S. Tzortzakis, have shown how this light beam, called a ring-Airy beam, can transform into light bullets.
The experiment, detailed in the journal Nature Communications, followed a previous study in the field carried out back in 2011, when scientists demonstrated an Airy beam in the form of a ring that could self-focus into a sharp focal point when in the linear regime. This time, the researchers examined the properties of ring-Airy beams in the non-linear regime, which appeared to be even more remarkable. In particular, the scientists found that the beam wavepacket transforms into a high-intensity light bullet that propagates neither in space nor in time after travelling distances substantially longer than Gaussian beams, which are used in a typical laser.
The experiment also revealed that the focus position of the ring-Airy beam is not shifted almost as much as it is for Gaussian beams when the input power is raised. By carrying out additional experiments, the scientists also confirmed that they can mathematically predict the focus position of the beam for a particular input power.
These ring-Airy beam light bullets could be used in a broad array of optical applications, from precision material processing to attosecond drivers, as well as in areas such as laser micromachining and harmonic generation.