Researchers have unravelled a new form of light previously unknown and this finding could pave way for circuitry that work on photons rather than electrons.

Researchers at Imperial College London revealed through their study published in Nature Communications that it is possible to create a new form of light by binding light to a single electron and this form of light will have properties of a photon as well as electron. While circuitry that works on photons could be one of the possible applications, researchers say that the more attractive application would be to study quantum physical phenomena, which govern particles smaller than atoms, on a visible scale.

Normally, light interacts with a whole host of electrons present on the surface and within normal material, but when theoretical physics is used to model the behaviour of light and a recently-discovered class of materials known as topological insulators, it could be possible to make light interact with just one electron on the surface. This particular opportunity would enable scientists to create a coupling that merges some of the properties of the light and the electron.

Normally, light travels in a straight line, but when bound to the electron it would instead follow its path, tracing the surface of the material. Researchers have modelled this interaction around a nanoparticle – a small sphere below 0.00000001 metres in diameter – made of a topological insulator. Findings indicate that light takes the property of the electron and vice versa.

Artistic image of light trapped on the surface of a nanoparticle topological insulator. CREDIT: Vincenzo Giannini
Artistic image of light trapped on the surface of a nanoparticle topological insulator. CREDIT: Vincenzo Giannini

Normally, as electrons are travelling along materials, such as electrical circuits, they will stop when faced with a defect. However, Imperial College researchers discovered that even if there were imperfections in the surface of the nanoparticle, the electron would still be able to travel onwards with the aid of the light. If this could be adapted into photonic circuits, they would be more robust and less vulnerable to disruption and physical imperfections.

Researchers are of the opinion that the new form of light could be scaled up so that the phenomena could observed much more easily. Currently, quantum phenomena can only be seen when looking at very small objects or objects that have been super-cooled, but this could allow scientists to study these kinds of behaviour at room temperature.