University of California, Riverside, researchers have made a very small breakthrough in the way computers work… one that might lead to big changes soon. They’re using atom-thin sheets of carbon to create an entirely new kind of logic circuit:
Graphene is a single-atom thick carbon crystal with unique properties beneficial for electronics including extremely high electron mobility and phonon thermal conductivity. However, graphene does not have an energy band gap, which is a specific property of semiconductor materials that separate electrons from holes and allows a transistor implemented with a given material to be completely switched off.
“Most researchers have tried to change graphene to make it more like conventional semiconductors for applications in logic circuits,” [Alexander Balandin, a professor of electrical engineering,] said. “This usually results in degradation of graphene properties. For example, attempts to induce an energy band gap commonly result in decreasing electron mobility while still not leading to sufficiently large band gap.”
“We decided to take alternative approach,” Balandin said. “Instead of trying to change graphene, we changed the way the information is processed in the circuits.”
Modern digital logic, which is used in computers and cell phones, is based on Boolean algebra implemented in semiconductor switch-based circuits. It uses zeroes and ones for encoding and processing the information. However, the Boolean logic is not the only way to process information. The UC Riverside team proposed to use specific current-voltage characteristics of graphene for constructing the non-Boolean logic architecture, which utilizes the principles of the non-linear networks.
“Boolean logic” is true/false, on/off binary thinking. Non-linear networks have in-betweens – a little of this, a little of that – and solve problems all at once, rather than the linear, if-this-then-that processes our current silicon chips do. (They just work through their lines very quickly, so it can seem like they’re doing everything all at once.)