An international team of scientists from the French National Center for Scientific Research and the Karlsruhe Institute of Technology in Germany has developed a new prototype lens using graphene.
This prototype lens is capable of focusing an electron stream like the manner optical lenses focus light. It is based on the fact that a graphene layer gets strained when stretched, thus enabling it to function as a 2D lens for electrons. The study has been reported in Applied Physics Letters, a journal of the American Institute of Physics.
Graphene, a one-atom-thick carbon material, is a remarkable conductor wherein electrons traverse freely in straight lines across its surface. A theory hypothesized that highly strained graphene hinders the electron flow and alters the trajectory of electrons. Researchers believed that this phenomenon can be utilized for focusing electrons towards a fine point like the way optical lenses refract or bend light towards a point.
To fabricate the prototype lens, the international research team first developed a deformed graphene carpet that effectively covers a silicon-carbide wafer’s hexagonal nano-holes. Graphene experienced strain when its areas assumed the form of the nano-holes in the wafer. The team discovered that the graphene lens’ focal length can be controlled by altering its geometry.
The new prototype lens paves the way to develop high-speed electronic applications, wherein strained graphene can be used as a transport medium to exchange information between various components in a circuit. The new technique allows electrons to flow freely like that of light moving in a vacuum, which is contrary to conventional information exchange where the path of electrons traversing cables needs a short to cross.