By focusing an ultrashort laser beam onto a graphene oxide polymer, researchers have developed a new material for multimode optical recording.
Swinburne University of Technology researchers have shown the potential of a new material for transforming secure optical information storage.
In their latest research paper published in Scientific Reports, researchers Xiangping Li, Qiming Zhang, Xi Chen and Professor Min Gu demonstrated the potential to record holographic coding in a graphene oxide polymer composite.
“Conventionally, information is recorded as binary data in a disc. If the disc is broken, the information cannot be retrieved,” Director of the Center for Micro-Photonics at Swinburne, Professor Min Gu, said.
Graphene oxide is similar to graphene, discovered by Andre Geim and Konstantin Novoselov, who received the 2010 Nobel Prize in Physics for this groundbreaking discovery. Graphene is very strong, light, flexible, nearly transparent, and is an excellent conductor of heat and electricity.
Graphene oxide has similar properties, but also has a fundamental fluorescent property that can be used in bioimaging and for multimode optical recording.
By focusing an ultrashort laser beam onto the graphene oxide polymer, the researchers created a 10-100 times increase in the refractive-index of the graphene oxide along with a decrease in its fluorescence. (The refractive index is the measure of the bending of light as it passes through a medium.)
To demonstrate the feasibility of the mechanism, the researchers encoded the image of a kangaroo in a computer generated hologram. The hologram was then rendered as a three-dimensional recording to the graphene oxide polymer. The encrypted patterns in the hologram could not be seen as a normal microscope image, but could be retrieved in the diffracted mode.
Publication: Xiangping Li, et al., “Giant refractive-index modulation by two-photon reduction of fluorescent graphene oxides for multimode optical recording,” Scientific Reports 3, Article number: 2819; doi:10.1038/srep02819
Source: Swinburne University of Technology
Image: Xiangping Li, et al., doi:10.1038/srep02819