Graphene never ceases to surprise us when it comes to optics and photonics.
- Andrea Ferrari
Graphene, among other materials, can capture particles of light called photons, combine them, and produce a more powerful optical beam. This is due to a physical phenomenon called optical harmonic generation, which is characteristic of nonlinear materials. Nonlinear optical effects can be exploited in a variety of applications, including laser technology, material processing and telecommunications.
Although all materials should demonstrate this behaviour, the efficiency of this process is typically small and cannot be controlled externally. Now, researchers from the University of Cambridge, Politecnico di Milano and IIT- Istituto Italiano di Tecnologia have demonstrated that graphene not only shows a good optical response but also how to control the strength of this effect using an electric field. Their results are reported in the journal Nature Nanotechnology. All three institutions are partners in the Graphene Flagship, a pan-European project dedicated to bringing graphene and related materials for commercial applications.
Graphene – a form of carbon just a single atom thick – has a unique combination of properties that make it useful for applications from flexible electronics and fast data communication, to enhanced structural materials and water treatments. It is highly electrically and thermally conductive, as well as strong and flexible.
Researchers envision the creation of new graphene optical switches, which could also harness new optical frequencies to transmit data along optical cables, increasing the amount of data that can be transmitted. Currently, most commercial devices using nonlinear optics are only used in spectroscopy. Graphene could pave the way towards the fabrication of new devices for ultra-broad bandwidth applications.
Image: Graphene
Credit: AlexanderAlUS
Reproduced courtesy of the University of Cambridge