London | Graphene out-performs superconductors when carrying high-frequency electrical signals without losing any energy, a new study has found suggesting that the wonder material may help develop next-generation amplifiers and bio-sensors.
Discovered in 2004, graphene – which measures just an atom in thickness and is around 100 times stronger than steel – has been identified as having a range of potential uses across the engineering and health sectors. Since graphene lacks band-gap, which allows electrical signals to be switched on and off using silicon in digital electronics, scientists say it seems most applicable for applications ranging from next generation high-speed transistors and amplifiers for mobile phones and satellite communications to ultra-sensitive biological sensors.
An accurate understanding of the electromagnetic properties of graphene over a broad range of frequencies (from direct current to over 10 gigahertz) has been an important quest for several groups around the world, said principal investigator Shakil Awan, from the Plymouth University in UK. 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, Awan said.
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, he said. The results are now being exploited in developing high-speed and efficient low noise amplifiers, mixers, radiation detectors and novel bio-sensors.
The findings my help develop highly-sensitive graphene bio-sensors for early detection of dementia (such as Alzheimer’s disease) compared to current methods. Graphene is ideally suited for this as its room temperature thermal noise is smaller than any other known material, enabling the sensitive detection of tiny numbers of antibody-antigen interactions to indicate the likelihood of a patient to develop dementia in the future.