Researchers at the Georgia Institute of Technology and the University of Tianjin in China have developed a nanoelectronics platform that could potentially replace silicon in computer chips, according to a study published in Nature Communications. The technology, based on graphene – a single sheet of carbon atoms – is compatible with conventional microelectronics manufacturing and could lead to the production of smaller, faster and more efficient computer chips. It also has potential applications in quantum and high-performance computing. The team may have also discovered a new quasiparticle in the course of their research.
Graphene, which is composed of the strongest chemical bonds known, has long been seen as a promising replacement for silicon due to its ability to be miniaturized to a greater extent, enabling smaller devices that can operate at higher speeds and produce less heat. In 2001, Regents’ Professor in the School of Physics at Georgia Tech, Walter de Heer, proposed an alternative form of electronics based on epitaxial graphene, or epigraphene. Researchers discovered that electric currents could flow without resistance along epigraphene’s edges and that graphene devices could be seamlessly interconnected without metal wires.
To create the new nanoelectronics platform, the team used a modified form of epigraphene on a silicon carbide crystal substrate and produced silicon carbide chips from electronics-grade silicon carbide crystals. Electron beam lithography, a method commonly used in microelectronics, was used to carve the graphene nanostructures and weld them to the silicon carbide chips. A cryogenic apparatus was then used to measure the electronic properties of the graphene platform from near-zero temperatures to room temperature.
The electric charges observed in the graphene edge state were similar to photons in an optical fiber, and the researchers found that they travelled for up to ten micrometers without scattering. The team believes that this property could be used to create highly efficient and ultra-fast graphene transistors that could operate at very low power levels.
The researchers also discovered a new quasiparticle in the graphene edge state that has a spin, but no charge. This quasiparticle, called a “spinon”, could be used to encode and process quantum information and could potentially lead to the development of quantum computers.