Researchers at Radboud University Nijmegen in the Netherlands believe that lasers will one day take over conventional magnetic data writers in hard disk drives. In laboratory experiments, they used laser light to write data to a magnetic hard drive at very high speeds. The technique works because the photons transmitted by the laser actually carry angular momentum, allowing them to interact with the hard drive. Also, each laser pulse heats a tiny space on the disk just enough to make changing its polarity a little easier. Reversing the polarity of the laser pulses is effectively the equivalent of either a 1 or a 0 of binary code on the disk storage medium.
The researchers managed to transfer data at intervals of about 40 femtoseconds (quadrillionths of a second), about 100 times faster than conventional magnetic transfers. One drawback is that the footprint of the laser pulse on the disk is about 5 microns wide, which is considerably larger than the footprint produced by existing data-transfer systems. But physics doctoral candidate and co-author Daniel Stanciu says the team is working on improvements in the technology that should reduce the footprint's size to about 10 nanometers, and he expects to see a working prototype within a decade.
News source: AAAS