Nano light stores data in polymer

Researchers from the University of Pisa in Italy have shown that it is possible to write lots of information in very little space using a thin film of polymer and polarized blue light.

They used a near-field scanning optical microscope to aim a nanoscale spot of polarized blue light on a polymer. The light caused the polymer molecules it hit to change shape and line up. Aligned and non-aligned molecules could represent the 1s and 0s of digital information.

The reversible process could eventually be used in rewritable data storage devices that could hold more than a trillion bits per square inch, according to the researchers. That's about 2,000 times more than today's DVDs, which hold 537 million bits per square inch.

The researchers used the method to scribe 100-nanometer lines into a polymer film. The method could enable marks as small as 10 nanometers. The medium retained data for several months, and is likely to remain stable long enough for practical applications, according to the researchers.

The researchers are working on increasing reading and writing rates from a slow 100 bits per second. Today's rewritable CD's record at over one million bits per second.

The method could be used in practical applications in two to five years, according to the researchers. The work appeared in the May 12, 2003 issue of Applied Physics Letters.