British Physicists Build a Machine that Reveals Unusual Qualities of Light

Researchers from the National Physics Laboratory (NPL) in the United Kingdom and Heriot-Watt University in Edinburgh have seen how light breaks its usual symmetrical patterns within devices called optical ring resonators.

In physics, waves can behave in curious ways when they echo within the right kind of space, something that can be applied to the bounce of sound on ceilings, or to the light that pursues its tail in a circle. A team of researchers from the National Physics Laboratory of the United Kingdom have revealed unusual qualities in light that could set a precedent for the development of optical technology and entirely new electronic applications, in various fields such as telecommunications, fiber optics or computing.

To this end, this group of scientists has built a ring-shaped machine in which the pulses of light rotate in circles and the normal rules that govern the habitual behavior of light do not apply. Under normal circumstances, the light is symmetric: it behaves in the same way in both directions in time-a concept that is known under the term time inversion symmetry-and on the other hand, it shows polarization in relation to the movement of the wave , providing another kind of symmetry.

Under the new device created by this set of British physicists, light loses its time-reversing symmetry and changes its polarization, forming ellipses. Within this machine, light waves rotate in circles and resonate with each other, generating unusual effects that do not occur in the outside world. Although it was already known from other investigations that light loses its time-reversing symmetry as it bounces inside the optical rings, it has not been shown that this phenomenon can occur at the same time as the spontaneous changes in polarization.

This study creates new ways for optical circuits that could be applied in quantum computers and atomic clocks, improving the accuracy of new electronic devices, since “optics has become an important part of telecommunications networks and computer systems”, according to revealed researcher Pascal Del’Haye of NPL. “Understanding how we can manipulate light in photonic circuits will help unlock a lot of new technologies, including better sensors and new quantum capabilities, which will be increasingly important in our daily lives.”