Ultrafast lasers enable rapid, photo-magnetic optical storage

University of Bialystok in Poland and colleagues used cool ultrafast lasers to store information on garnet crystal.

Hard disk drives have been the data storage staple for decades, but new nonthermal photomagnetic optical storage techniques are being developed. (Image credit: Daniel Sambraus /Getty Images)
Hard disk drives have been the data storage staple for decades, but new nonthermal photomagnetic optical storage techniques are being developed. (Image credit: Daniel Sambraus /Getty Images)

IMAGE: Hard disk drives have been the data storage staple for decades, but new nonthermal photomagnetic optical storage techniques are being developed. (Image credit: Daniel Sambraus /Getty Images)

Andrzej Stupakiewicz from the University of Bialystok in Poland and colleagues used precisely tuned laser pulses to store information on garnet crystal at speeds 1000 times faster than magnetic hard drives with very little heat. The work was published in Nature.

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In data storage devices such as the hard drive in your laptop, information is written and read in magnetic units of information called bits. When data is stored, an electromagnet flips the magnetic orientation of small patches on a spinning disc. Magnetization in one direction is read as a 1 and in another direction, 0, writing data in binary code.

The problem is this technique can be relatively slow, energy-intensive, and generate heat. And while ultrafast lasers can be fired at metals to force them to flip a memory bit, the process still generates heat. Stupakiewicz’s team enlisted the help of lasers to write magnetic data bits too, but in a slightly different manner. Instead of using a high-temperature laser on a metal, they used polarized light to flip the magnetization on points of a garnet material.

Stupakiewicz's team showed laser light polarized in one direction wrote a 1 while a different direction wrote a 0 extremely quickly--fewer that 20 trillionths of a second--and with very little heat of less than six joules per cubic centimeter. And because little excess heat was generated, the device was also very energy efficient.

The researchers anticipate that this research will open up many opportunities for the design and development of materials and methods in the field of opto-magnetic recording. "But we'll probably be waiting a while for it to hit shelves," says James Thom, a computer scientist from RMIT University in Melbourne, Australia. "Although you may be able to write the tape reasonably quickly, to retrieve it, you need to go to the bit of tape that you need," he explains. "A lot of the speed of a disc drive, for example, depends on the speed at which the disc is spinning."

SOURCE: COSMOS Magazine; https://cosmosmagazine.com/technology/cool-laser-writes-data-in-20-trillionths-of-a-second?utm_source=MIT+TR+Newsletters&utm_campaign=1f435d0b04-The_Download&utm_medium=email&utm_term=0_997ed6f472-1f435d0b04-153908949

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