UK Team Finds Tiny Atomic Changes Can Create Smarter Wireless Antennas

A team of researchers from the Queen Mary University of London have discovered a new way to make wireless communication devices, such as antennas, more adaptable by making tiny atomic changes to the structure of a material that can “dramatically improve its ability to respond to electrical signals“. The work could have applications in everything from home Wi-Fi to satellites and mobile broadband networks etc.

The team is said to have focused on a ceramic material called strontium tantalate. By replacing a small number of atoms with slightly smaller calcium atoms, they created tiny distortions in the material’s structure. Although these changes occur at the atomic scale, they have a major effect on how the material behaves and could help create a new generation of wireless devices that can “change frequency on demand“.

The researchers found that these atomic-scale distortions create small regions of electrical activity, known as polar nanoclusters, inside a material that would normally be electrically inactive. These nanoclusters can quickly respond to electric fields, allowing the material’s properties to be tuned when needed.

Interestingly, it only takes a very small amount of calcium to achieve the effect. The best-performing lead-free material contained just 8% calcium, yet it showed a rare combination of strong tunability, low energy loss and stable performance across a wide range of frequencies. This is significant because engineers have previously faced a trade-off: materials that are easy to tune often waste energy or perform poorly at high frequencies. But the new research appears to overcome this.

Professor Yang Hao, Author of the Study, explained:

“This is a bit like finding a way to add dimmer switches to a system that previously only had an on and off setting. Small structural changes give us a much greater level of control.”

Dr Hangfeng Zhang, Lead Author of the Study, said:

“Wireless technologies are becoming increasingly sophisticated, and that creates a need for materials that can adapt quickly and efficiently. Our research shows that small changes at the atomic level can have a surprisingly large effect on performance. We hope this approach will help support the development of smarter antennas, tunable communication devices and other technologies that need to respond to changing demands in real time.”

Materials that can adjust their properties in real time like this could thus help modern or future wireless network links to become more efficient and adaptable. But interestingly this research reflected more than just a lab test, as the same team has already incorporated the material into prototype antennas and microwave devices, which demonstrated that the operating frequency could be changed using electrical voltage or temperature.

The research was carried out by scientists from the School of Electronic Engineering and Computer Science and the School of Engineering and Materials Science at Queen Mary University of London. A related paper is due to be published today in Science Advances. The research was supported by the Engineering and Physical Sciences Research Council (EPSRC) and the Royal Academy of Engineering.