Scientists have discovered new particles that could form the basis of a future technological revolution based on photonic circuits and lead to the development of ultra-fast computational methods based on light. Computing today is based on electronics, where electrons are used to encode and carry information. Due to certain fundamental limitations, such as the loss of energy during resistive heating, it is expected that photons will come to replace electrons and there will be futuristic computers based on light that will be much faster and more efficient than electronic ones.
Physicists at the University of Exeter have taken an important step towards this goal by discovering new particles that are half light, half matter and that inherit a number of notable properties from graphene.
What will replace electronics?
The scientists' discovery opens the door to the development of photonic circuits that use alternative particles known as massless Dirac polaritons to transmit information instead of electrons.
Dirac polaritons originate in honeycomb metasurfaces, which are ultra-thin materials engineered with nanoscale structures that are much smaller than the wavelength of light.
A unique property of Dirac particles is that they mimic massless relativistic particles, allowing them to travel very efficiently. This fact makes graphene one of the most conductive materials known to man.
However, despite the unusual properties of such materials, they are extremely difficult to control. For example, in graphene, it is impossible to turn electric currents on and off using a simple electric potential, which limits the potential use of graphene in electronic devices. This fundamental flaw - lack of customization - has been successfully overcome by physicists at the University of Exeter.
Scientists have shown that by embedding honeycomb metasurfaces between two reflective mirrors and changing the distance between them, it is possible to tune the fundamental properties of Dirac polaritons in a simple, controllable and reversible way. This was also achieved because Dirac polaritons are a mixture of light and matter components. It is this hybrid nature that makes it possible to tune their fundamental properties by manipulating only the light component, which cannot be done in graphene.