In their normal form, photons do not have mass, they move at the speed of light and do not interact with each other in any way. However, a few years ago the phenomenon of “photon molecules” was discovered – structures that consist, as it were, of a pair of photons. At the Massachusetts Institute of Technology, an experiment was made to generate such molecules under ideal conditions and obtained “photon triplets”, which can be conditionally called a new form of matter and light simultaneously.
The rubidium cloud was cooled to almost absolute zero, so that the atoms of the substance became almost immobile, after which was sent there a very weak laser beam. It emits just a few photons per flash, which are easy to track. And it turned out that at the exit from the cloud photons were grouped in 2 or 3, acquired a mass, albeit insignificant, and slowed down because of this 100,000 times.
The parameter of the phase, the photon interaction coefficient, for triplets was three times larger than for photon pairs – they really did not accidentally “coalesce”, but acted as a single structure. Scientists suggested that when passing through a cloud of atoms, photons were subjected to a certain effect and turned into “polaritons”. This is a term from quantum theory, a particle with the signs of light and matter at the same time, so it can interact with like-minded people.
Polaritons retained their properties beyond the cloud of rubidium, but their detailed behavior is a matter of the following experiments. While scientists are trying to include this discovery in the existing framework of understanding the world. If there is a “space-time”, can there be “matter-light”? And if polaritons can be described by the rules of quantum calculus, is there a chance to use them in quantum computers and similar future applications?js.src = “&version=v2.8”; 'script', 'facebook-jssdk'));