Speed limits apply not only to traffic. There are limitations on the control of light as well, in optical switches for internet traffic, for example. Physicists at Chalmers University of Technology now understand why it is not possible to increase the speed beyond a certain limit – and know the circumstances in which it is best to opt for a different route.
Light and other electromagnetic waves play a crucial role in almost all modern electronics, for example in our mobile phones. In recent years researchers have developed artificial speciality materials – known as optomechanical metamaterials – which overcome the limitations inherent in natural materials in order to control the properties of light with a high degree of precision. For example, what are termed optical switches are used to change the colour or intensity of light. In internet traffic these switches can be switched on and off up to 100 billion times in a single second. But beyond that, the speed cannot be increased any further. These unique speciality materials are also subject to this limit.
“Researchers had high hopes of achieving higher and higher speeds in optical switches by further developing optomechanical metamaterials. We now know why these materials failed to outcompete existing technology in internet traffic and mobile communication networks,” says Sophie Viaene, a nanophotonics researcher at the Department of Physics at Chalmers.
Read more at Chalmers University of Technology
Image: Chalmers researchers Sophie Viaene and Philippe Tassin recently published their research findings in nanophotonics in the well-respected journal Physical Review Letters. They have determined what direction to take in their area of research. (Credit: Mia Halleröd Palmgren/ Chalmers University of Technology)