Researchers at Swinburne University of Technology have demonstrated 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.
Director of the Centre for Micro-Photonics at Swinburne, Professor Min Gu explains that conventionally, information is recorded as binary data in a disc; the information cannot be retrieved if the disc is broken. This is a major operational cost in big data centres, which consist of thousands of disc arrays with multiple physical duplicates of data. The new material allows the development of super-discs, which will enable information to be retrieved even from broken pieces.
Graphene oxide is similar to graphene, discovered by Andre Geim and Konstantin Novoselov, who received the 2010 Nobel Prize in Physics for this ground-breaking discovery. Graphene is very strong, light, flexible and nearly transparent, and is an excellent conductor of heat and electricity.
Possessing similar properties, graphene oxide also has a fundamental fluorescent property that can be used in bio-imaging and multimode optical recording. By focusing an ultra-short 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.
According to Professor Gu, the unique feature of the giant refractive index modulation together with the fluorescent property of the graphene oxide polymer offers a new mechanism for multimode optical recording. 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.
Professor Gu says the giant refractive index of this material shows promise for merging data storage with holography for security coding, not only boosting the level of storage security, but also helping to reduce the operation costs of big data centres that rely on multiple physical duplicates to avoid data loss.
The researchers say it could also revolutionise flat screen TV and solar cell technology.
This research has been funded under the Australian Research Council Discovery Project scheme and the Australian Research Council Laureate Fellowship program.