500 terabytes in the size of a CD, a new method for writing on glass

Researchers fromSouthampton University have developed (here the publication) a new method of writing via a fast and efficient laser that could allow you to store up to 500TB of data in the size of a CD, that is, with one 10,000 times the density of Blu-Ray technology. The laser allows you to save information in high-density nanostructures on the glass.

According to researcher Yuhao Lei, the new data storage technology it could be useful for saving information contained in national archives, museums and libraries. We are therefore not talking about home applications, but about areas where magnetic tapes are still used today. The method of writing it is called 5D because it contains two optical dimensions plus three spatial dimensions. The new approach can write at speeds of 1 million voxels per second, that is, write 230 kilobytes of data per second.

The method made it possible to record 5 GB of data in a one-inch glass sample. The four squares in the photo each measure just 8.8 x 8.8mm

“The physical mechanism we use is generic,” Lei said. “Therefore, we anticipate that this energy-efficient writing method could also be used for rapid nanostructuring in transparent materials for applications in 3D integrated optics and microfluidics.”

5D optical storage on transparent materials had already been demonstrated, but not writing with sufficient speed and density for real-world applications. To overcome these obstacles, the researchers used a femtosecond laser with a high repetition rate to create small “pits” containing a single nanolamella-like structure with dimensions of 500 by 50 nanometers.

Instead of using the femtosecond laser to write directly into the glass, the researchers harnessed the light for produce an optical phenomenon known as “near-field enhancement”, in which a nano-slat-like structure is created by a few faint pulses of light, starting with an isotropic nano-vacuum generated by a single micro-explosion. The use of that optical phenomenon to create the nanostructures minimized the thermal damage caused by other approaches who use lasers with a high repetition rate.

Since the nanostructures are anisotropic, they produce a birefringence that can be characterized by the orientation of the slow axis of light (4th dimension, corresponding to the orientation of the structure similar to a nanolamella) and by the delay force (5th dimension, defined by the dimension of the nanostructure). When the data is written into the glass, the orientation of the slow axis and the strength of the delay can be controlled by the polarization and the intensity of the light respectively.

“This new approach improves the speed of writing data to a level appropriate to reality, then we can write tens of gigabytes of data in a reasonable time“said Lei.” Highly localized nanostructures allow for greater data capacity because more voxels can be written in a unit volume. Furthermore, the use of pulsed light reduces the energy required for writing“.

The researchers used their new method for write 5 GB of text data on a glass disc the size of a conventional CD with a reading accuracy of nearly 100%. Each voxel contained four bits of information and each two voxels corresponded to a text character. With the writing density provided by the new method, the disk would be able to hold 500TB of data, adjustable in approx 60 days.

At the University of Southampton they are working for increase the writing speed of their method and make the technology applicable in everyday life. At the same time, faster methods of reading archived data are being conceptualized.

PREV Posina. Exploitation to the limit of slavery even for minors in the company that bottles water
NEXT Betty White, the ‘Golden girl’ actress of American TV, was about to turn 100