Laser-driven hard drives

“Ultra-rapid pulses of polarized light fired from lasers, new tests show, can outperform conventional magnetic data writers by as much as two orders of magnitude.

Researchers at Radboud University Nijmegen in the Netherlands think they’ve found another candidate. 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—thereby storing a bit of data—a little easier. The key is reversing the polarity of the laser pulses, which can produce 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, or quadrillionths of a second, about 100 times faster than conventional magnetic transfers, the researchers report in a paper accepted for publication by Physical Review Letters.”