The first material with a refractive index of 0

For the first time, physicists have developed a metamaterial with a zero refractive index of light. This can lead to the creation of a new class of optical (photonic) computers , in which information is transmitted at extremely high speed.

The new metamaterial allows you to overcome the limitations of existing designs of photonic computers, in which the resulting photons have to be converted to electrons, because of which all speed advantage is lost. Here, photons can be manipulated in every way and do different unusual things with them.

“Light is usually hard to compress or process,” saysEric Mazur of Harvard University, a leading author of scientific work, “but this metamaterial allows you to process light when transmitting from one chip to another: compress it, bend, twist, change the diameter of the beam from macro to nanoscale.”

The metamaterial is made of silicon columns embedded in a polymer matrix and wrapped in a gold film.



According to the authors, the light waves in the material travel "infinitely fast" without violating the laws of physics. Of course, by “infinite” we mean the phase velocity of the wave, and not the real speed of light.



Everyone knows that the speed of light in a vacuum is 299,792,458 meters per second. But there is still such an indicator as phase velocity- the velocity of the crests of the waves in space along a given direction. For example, when air gets into water, light waves are flattened (compressed) by about 30%. That is, the phase velocity decreases by 30% - respectively, the refractive index of water is approximately 1.3.

What happens in metamaterial with a zero refractive index? Simply put, rather strange things happen. The light wave, as it were, is straightened, peaks and troughs disappear on it, it turns into a straight line, the fluctuations of which are a factor of time, not space. Wave straightening makes it easy to manipulate without loss of energy. Theoretically, such characteristics mean the almost endless potential of using a new metamaterial in industry: from telecommunications to quantum computing. For example, quantum emitters in an environment where there is no phase advance can emit photons that are always phase locked to each other, saysPhilip Munoz, one of the authors of the scientific work: “It can also improve entanglement between quantum bits, because the incoming light waves have infinite length and efficiently propagate in the medium, allowing the entanglement of particles even far apart”.

The scientific work "On-chip zero-index metamaterials" was published on October 19, 2015 in the journal Nature Photonics ( pdf ).