Volumetric optical data storage via sequential two-photon absorption in new aggregate aluminum oxide:carbon,magnesium crystals

Scope and method of study. The goal of this project is to understand the properties of the new aggregate Al2O 3:C,Mg crystals in order to produce the next generation commercial storage devices. Since current areal storage technologies are at the theoretical limits of its capabilities it is essential to investigate other alternatives in order address the increasing demand for storage capacity. Therefore, in order to overcome current limitations we employ volumetric storage via two photon absorption along with a one photon excitation confocal fluorescence detection scheme. As the name implies, volumetric storage utilizes three dimensions thus allowing for storage of multiple layers of data within the volume of the crystal media. In addition to the demand for higher capacity, the rate at which data can be read from such storage media is equally important for future high throughput applications. This paper will discuss some preliminary results obtained while working as a research assistant at Landauer, inc.; Findings and conclusions. The fluorescence signal amplitudes were strongly dependent on the color center concentrations. The bit half widths were dependent on the amount of energy delivered. Data transfer rates were demonstrated at a rate of 2.5 Mbit/s without the use of any signal filtering or processing. In order to demonstrate the nonlinear nature of sequential two photon absorption it is necessary to use laser power levels less than 1 mW or at power levels higher than 10 mW for recording.