Femtosecond-laser writing in fused quartz has resulted in high-capacity storage that could last up to 13 billion years, according to researchers. Three separate accounts of this development have just been published by SPIE.
An article in the online SPIE Newsroom by scientists at the University of Southampton (UK) Optoelectronics Research Centre is available at http://spie.org/5d. A video interview with professor and group leader Peter Kazansky was also published this week. Finally, the group's SPIE Proceedings paper is freely available in the SPIE Digital Library.
The approach takes advantage of the plasmonic properties of gold or silver nanoparticles, which are embedded within the storage material. The "5D" aspect of the method is based on three spatial and two optical dimensions. Kazansky and colleagues explain further in their article just published on SPIE Newsroom:
"When the data-recording femtosecond laser marks the glass, it makes a pit with a nanograting. This nanograting produces birefringence that is characterized by two additional parameters. The slow-axis orientation introduces a fourth dimension, and the strength of retardance-defined as a product of the birefringence and the length of the structure-forms a fifth dimension. These two parameters are controlled during recording by the polarization and light intensity, respectively."
The polarization-multiplexed writing has been demonstrated by using self-assembled nanogratings, which are produced via ultrafast-laser writing in fused quartz. The quartz and embedded nanogratings are extremely resistant to decay, and through heating tests, their longevity has been estimated to reach well beyond a billion years, according to Kazansky.
Kazansky calls the discovery of the nanogratings' behavior "serendipitous" and still mysterious. "They behave like a birefringent crystal," he says, but "the exact mechanism still is not clear."
J. Zhang ; A. Čerkauskaitė ; R. Drevinskas ; A. Patel ; M. Beresna ; P. G. Kazansky. Eternal 5D data storage by ultrafast laser writing in glass. Proc. SPIE 9736, Laser-based Micro- and Nanoprocessing X, 97360U (March 4, 2016); doi:10.1117/12.2220600
P. Kazansky, A. Cerkauskaite, M. Beresna, R. Drevinskas, A. Patel, J. Zhang and M. Gecevicius, Eternal 5D data storage via ultrafast-laser writing in glass. SPIE Newsroom, 10 March 2016, doi:10.1117/2.1201603.006365
Video interview with Peter Kazansky
SPIE is the international society for optics and photonics, an educational not-for-profit organization founded in 1955 to advance light-based science, engineering, and technology. The Society serves nearly 264,000 constituents from approximately 166 countries, offering conferences and their published proceedings, continuing education, books, journals, and the SPIE Digital Library. In 2015, SPIE provided more than $5.2 million in support of education and outreach programs.
Public Relations Manager
+1 360 685 5478