Zero-bandgap graphene for infrared sensing applications

Abstract

Recently, scientists have been looking for novel materials to improve the performance of optoelectronic devices. Graphene opens up new possibilities for infrared (IR) sensing applications. With a zero-bandgap graphene, electron-hole pairs can be generated easily by low energy photons such as middle-wave infrared signal. We have used an electricfield- assisted method to manipulate graphene between metal microelectrodes successfully. When a graphene contacts with a metal, a built-in potential forms at the interface and it separates the electron-hole pairs that flow as photocurrents. Based on this principle, we demonstrated using the graphene-based devices for infrared detection under a zero-bias operation. We also tried to apply the devices with positive and negative bias voltages, and results indicated the flow of photocurrent is independent of the polarity of the bias voltages. © 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).