updated 05:30 pm EST, Thu January 15, 2009
Laser hard drives coming
A new technology, still in its infancy, could revolutionize data storage devices, merging optical and magnetic technologies. A discovery made in 2006 by Dr. Daniel Stanciu and Dr. Frederick Hansteen that uses light to change the polarity of a magnet is being researched and worked on by physicists around the world. Called all-optical magnetization reversal, it could be applied to storage drives that are more reliable than current devices yet are thousands of times faster. The idea involves using a short laser pulse of about 40 femtoseconds in order to switch a magnet's polarity and therefore write data.
Two major hurdles exist, keeping the technology from becoming widespread, though they have been solved. One of the main issues is packaging a large and expensive femtosecond laser into the size of a conventional hard drive. While at an internship at Seagate in 2007, Stanciu and colleagues used less costly picosecond lasers to achieve their goals of switching magnets, making them feasible counterparts, at least initially.
The other issue involved focusing light below micron level while maintaining the laser beam's circularly polarized light the same. Plasmon antennas capable of doing so and available in 2007 caused the polarization, the switching of which allows for switching a magnet, to be lost. According to Stanciu, a research group led by Professor Thomas Ebbesen in Strasbourg, France built plasmon antennas that can act like quarter wave plates and focus circularly polarized light. Despite these fixes, Stanciu believes the industry is about five years from producing commercially-available laser hard drive hybrids.
Stanciu believes a laser hard drive using available components could be built fairly soon and reach a speed of about 1 Tbps, though the price of such a device is not mentioned. Today's range-topping hard drives can transfer data at about 1GBps, while high-end solid state drives are capable of about 2- or 3GBps. Eventually, femtomlaser drives could reach speeds as high as 100TBits/s or more. [via TheFutureofThings]
Illustration of a magneto-optical imaging set-up
An illustration demonstrating compact all-optical recording of magnetic bits