A team of researchers from different institutions in Spain and the USA notified that they have found a brand new property of light known as self-torque. The team’s research paper explained how they came to know about the property and what are the uses of it and their research paper was published in the journal Science.
Researchers knew about the properties of light such as wavelength before. By the property known as angular momentum scientists in the recent times came to know that lights can also be twisted. Vortex beams are that kind of beams that have highly structured angular momentum. They also have orbital angular momentum (OAM).
Vortex beams seem to be a helix which is surrounding a common center and when the beams strike a surface which is flat, they appear as doughnut-shaped. The scientists came to know about the new property of light while researching on OAM beams and while researching they found it out surprisingly where the lights were behaving in a way they had never noticed before. The scientists conducted a lot of experiments and the experiments were to fire two laser lights at the cloud formed by argon gas and by doing this it forced the beams to overlap. Thus they joined and they were emitted as a single beam from the other side of the argon cloud. The beam which resulted was a type of vortex beam.
The scientists then thought what would have happened if the lasers were a little bit out of synchronization and if the lasers had different orbital angular momentum. After this experiment emerged a beam which looked like a corkscrew with a twist which was gradually changing. When the beam hit the flat surface it looked similar to a crescent moon.
The researchers also noticed that it can be looked the other way round as a single photon which was at the front of the beam was revolving around its center slower than a photon which was at the back of the beam. The scientists named this new property as self-torque. This is not only a newly discovered property of light, but it is also the one which was never ever predicted. This technique can be used to modulate the orbital angular momentum of light in a way very similar to that of modulating frequencies in communicating tools. This could lead to the development of devices that are used to manipulate tiny materials.