0615_GRAPHENE [Electrified graphene a shutter for light]

Experiments at Rice University showed that voltage applied to a sheet of graphene on a silicon-based substrate can turn it into a shutter for both terahertz and infrared wavelengths of light. Changing the voltage alters the Fermi energy (Ef) of the graphene, which controls the transmission or absorption of the beam. The Fermi energy divides the conduction band (CB), which contains electrons that absorb the waves, and the valance band (VB), which contains the holes to which the electrons flow. Graphic by Rei Len/Rice University

About Mike Williams

Mike Williams is a senior media relations specialist in Rice University's Office of Public Affairs.