Graphene can transmit high frequency electrical signals without loss

"Our results for the first time not only confirm the theoretical properties of graphene but also open up many new applications of the material in high-speed electronics and bio-sensing."Shakil Awan, Plymouth University

Electrical signals transmitted at high frequencies lose none of their energy when passed through the 'wonder material' graphene, a study led by Plymouth University has shown. Discovered in 2004, graphene, which measures just an atom in thickness and is around 100 times stronger than steel, could have a range of potential uses across the engineering and health sectors.

Now this new study shows that graphene out-performs any other known material, including superconductors, when carrying high-frequency electrical signals compared to direct current, essentially transmitting signals without any additional energy loss. Since graphene lacks a band-gap, which is required for switching electrical signals on and off in digital electronics, academics say it appears most suitable for applications such as next generation high-speed transistors, amplifiers for mobile phones, satellite communications and ultra-sensitive biological sensors.

The study was led by Shakil Awan, a lecturer in the School of Computing, Electronics and Mathematics at Plymouth University (UK), alongside colleagues from the universities of Cambridge (UK) and Tohoku (Japan) and Nokia Technologies (Cambridge, UK).

"An accurate understanding of the electromagnetic properties of graphene over a broad range of frequencies (from direct current to over 10GHz) has been an important quest for several groups around the world," said Awan. "Initial measurements gave conflicting results with theory because graphene's intrinsic properties are often masked by much larger interfering signals from the supporting substrate, metallic contacts and measurement probes. Our results for the first time not only confirm the theoretical properties of graphene but also open up many new applications of the material in high-speed electronics and bio-sensing."

The study, published in 2D Materials, was funded by the EU Graphene Flagship, the European Research Council (ERC), the UK Engineering and Physical Sciences Research Council (EPSRC) and Nokia Technologies. The results are already being exploited in developing high-speed and efficient low noise amplifiers, mixers, radiation detectors and novel bio-sensors.

The latter is the focus of a three-year, £1 million project funded by the EPSRC, which is developing highly-sensitive graphene bio-sensors for early detection of dementias such as Alzheimer's disease. Graphene is ideally suited for this application as its room temperature thermal noise is smaller than any other known material, allowing the sensitive detection of tiny numbers of antibody-antigen interactions that can indicate the likelihood of a patient developing dementia in the future.

"Graphene devices for next generation wireless technologies (up to and beyond 10GHz) are progressing fast, " said Alan Colli from Nokia Technologies. "Our study has unlocked the fundamental behavior of graphene at high frequencies, which will be essential in the design and evaluation of future graphene-based wireless devices. This has only been made possible because of the multi-discipline expertise of the different groups based at Nokia, and in Plymouth, Cambridge and Tohoku universities."

This story is adapted from material from Plymouth University, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.