On the 10th anniversary of the "caught rainbow" - the slow light revolution

10 years ago, the German physicist Ortwin Hess, in his article "Storing light in a rainbow of metamaterials", suggested that light could be slowed down with new materials.

As you know, the speed of light in a vacuum is about 300 thousand km / sec, but when passing through transparent materials (water, glass), it slightly "slows down". According to scientists' calculations, if this speed is reduced by a factor of millions, then light could be used, for example, to transmit and store information.

Ortvin Hess and his colleagues Cosmas Tsakmakidis and Alan Boardman proposed using metamaterials that do not occur in nature to slow down light. According to scientists, with their help, you can not only slow down the light, but also "catch" it.

The process of creating a rainbow trap relies on nanoplasmonic structures, which exhibit special atypical properties when surrounded by "normal" materials. When light passes through a metamaterial, it experiences a slight recoil at the interface between the two materials. Roughly the same thing happens when a skier climbs up a steep snow-covered slope -

there is a small rollback for each step.

With regard to the metametrial, the following happens: when the light "rolls back", it gradually slows down along with all the components of its spectrum - and each color stops at its own point. As a result, the rainbow finds itself in a kind of "trap".

This effect of slowing down fast light has several very useful uses. For example, it can be used as a data transfer method. Another promising area is biomedical imaging. Sometimes, to obtain a clear image, it is necessary to increase the intensity of the laser beam, which can lead to the destruction of the object under study. By slowing down the light, these negative effects can be avoided.