Graphene-based transistor to revolutionise medical imaging?
1 min read
Researchers in the UK have crafted a new type of transistor with bistable characteristics, which they claim could revolutionise technologies such as medical imaging and security screening.
The device, created by a team from the Universities of Manchester and Nottingham, consists of two layers of graphene separated by an insulating layer of boron nitride just a few atomic layers thick.
The electron clouds in each graphene layer can be tuned by applying a small voltage. This can induce the electrons into a state where they move spontaneously at high speed between the layers.
Because the insulating layer separating the two graphene sheets is ultra thin, electrons are able to move through this barrier by quantum tunnelling. This process induces a rapid motion of electrical charge which can lead to the emission of high frequency electromagnetic waves.
"These new transistors exhibit the essential signature of a quantum seesaw, called negative differential conductance, whereby the same electrical current flows at two different applied voltages," explained Professor Laurence Eaves of the University of Nottingham. "The next step is to learn how to optimise the transistor as a detector and emitter."
