Graphene doesn’t naturally have a band gap but what if one could be created ? That would allow switching and allow the flow of electric current.
“In 2004, researchers discovered a super thin material that is at least a 100 times stronger than steel and the best known conductor of heat and electricity.
This means that the material, graphene, could bring faster electronics than is possible today with silicon.
But to truly be useful, graphene would need to carry an electric current that switches on and off, like what silicon does in the form of billions of transistors on a computer chip. This switching creates strings of 0s and 1s that a computer uses for processing information.
Purdue University researchers, in collaboration with the University of Michigan and the Huazhong University of Science and Technology, show how a laser technique could permanently stress graphene into having a structure that allows the flow of electric current.
This structure is a so-called “band gap.” Electrons need to jump across this gap in order to become conduction electrons, which makes them capable of carrying electric current. But graphene doesn’t naturally have a band gap.
Purdue researchers created and widened the band gap in graphene to a record 2.1 electronvolts. To function as a semiconductor such as silicon, the band gap would need to be at least the previous record of 0.5 electronvolts….
Cheng and his collaborators not only kept the band gap open in graphene, but also made it to where the gap width could be tuned from zero to 2.1 electronvolts, giving scientists and manufacturers the option to just use certain properties of graphene depending on what they want the material to do.
The researchers made the band gap structure permanent in graphene using a technique called laser shock imprinting, which Cheng developed in 2014 along with scientists at Harvard University, the Madrid Institute for Advanced Studies and the University of California, San Diego.
While still far from putting graphene into semiconducting devices, the technique grants more flexibility in taking advantage of the material’s optical, magnetic and thermal properties, Cheng said.”
Source: Physics Org / Provided by Purdue University
Image: Graphene, a super tough wonder material, hasn’t made it into electronics yet because it doesn’t conduct an electric current on its own. Researchers used a laser technique to permanently stress graphene into a structure that allows the flow of electric current. Credit: Purdue University/Gary Cheng