Graphene radios could unlock ‘Internet of Nano-Things’

By Jack Loughran
https://eandt.theiet.org/content/articles/2016/11/graphene-radios-could-unlock-internet-of-nano-things/

Miniature radios made from graphene that broadcast on the little-used terahertz band could enable an ‘Internet of Nano-Things’, according to a team at the University of Buffalo.

Their work centres on development of extremely small radios made of graphene and semiconducting materials that enable short-range, high-speed communication. 

The technology could ultimately reduce the time it takes to complete complex tasks, such as migrating files from one computer to another, from hours to seconds.

Other potential applications include implantable body nanosensors that monitor sick or at-risk people, and nanosensors placed on ageing bridges, in polluted waterways and other public locations, to provide ultra-high-definition streaming.

Although technological advancements have made wireless data transmission more efficient, bandwidth issues persist as wireless devices proliferate and the demand for data grows.

The solution could be found by using the terahertz band, which is sandwiched on the spectrum between radio waves (part of the electromagnetic spectrum that includes AM radio, radar and smartphones) and light waves (remote controls, fibre-optic cables and more).

The Buffalo team believes that graphene-based radios could help overcome the main problem with terahertz waves: they do not retain their power density over long distances.

Graphene is a two-dimensional sheet of carbon that, in addition to being incredibly strong, thin and light, has tantalising electronic properties. For example, electrons move 50 to 500 times faster in graphene compared to silicon.

In previous studies, researchers showed that tiny graphene antenna strips 10-100 nanometres wide and one micrometre long (pictured above), combined with semiconducting materials such as indium gallium arsenide, can transmit and receive terahertz waves at wireless speeds greater than one terabit per second.

However, to make these radios viable outside the laboratory, the antennas need other electronic components, such as generators and detectors that work in the same environment.

Josep Jornet, assistant professor at the University at Buffalo, is attempting to develop these components to make graphene radios a reality.

Jornet says thousands of these arrayed radios working together could allow terahertz waves to travel greater distances.

The nanosenors could be embedded into physical objects, such as walls and street signs, as well as chips and other electronic components, to create an 'Internet of Nano-Things'.

“For wireless communication, the terahertz band is like an express lane. But there’s a problem: there are no entrance ramps,” Jornet said.

“We’ll be able to create highly accurate, detailed and timely maps of what’s happening within a given system. The technology has applications in health care, agriculture, energy efficiency—basically anything you want more data on.”

In September, a team demonstrated how baking graphene in a microwave oven imbued it with properties that make it perfect for next-generation electronic and energy devices.