New gold DVDs and five dimensions

2009/07/01 Elhuyar Zientzia Iturria: Elhuyar aldizkaria

• Nanoteknologia
• Irudiak/Soinuak

They have invented a new way to store information on DVD and are developing it at the Australian University of Swinburne Technology. The new system can store more than 1 terabyte (one trillion bits), 10,000 times more information than DVDs that can now store more information.

Gold nanomatites have been used to increase both the capacity of the DVD without altering its size: nanomatites of different lengths have been introduced in the information writing layers. Due to the length and orientation that have the type of light that can absorb the sticks, different types of laser have been used to record the information.

On the one hand, they have "played" with the polarization of the laser. The laser with a determined polarization only interacts with gold particles oriented in its direction. In this interaction, the gold particles melt and those that were sticks become spheres. In this way, part of the DVD is recorded. However, the particles not oriented in the direction of this laser are out of use.

For your recording you can use a laser of another polarization or a light of another wavelength or color. In fact, the light of each wavelength only affects the sticks of a certain length. As with polarized light, the use of multi-color laser allows to store much information in a given space.

The researchers have used lasers of two polarizations and three colors to write on discs. In addition, as in the most powerful DVDs of the moment, they have been able to write the information in several layers. Thus, they have been able to store 140 gigabytes of information for every cubic centimeter of disk.

Writing in several layers is called writing in three dimensions. In recent years, experts have managed to add a fourth dimension by taking advantage of the possibilities offered by polarization or wavelength in discs. However, they did not get both to be used simultaneously on the same disk and reach the five dimensions. This has been achieved by Australian researchers with gold nanoparticles.