https://phys.org/news/2019-01-scientists-ways-shift.html

As outlined today in Physical Review Letters, NPL researchers investigated how light can be controlled in an optical ring resonator, a tiny device that can store extremely high light intensities. Just as certain 'whispers' can travel around a whispering gallery and be heard the other side, in an optical ring resonator wavelengths of light resonate around the device.

The first-of-its-kind study uses optical ring resonators to identify the interplay of two types of spontaneous symmetry breaking. By analysing how the time between pulses of light varied and how the light is polarised, the team has been able reveal new ways to manipulate light.