Progress toward terabit-rate high-density recording

Research is closing in on the next-generation of ultra-high-density magneto-optical storage devices that could store more than 6,000 Terabits (6 petabits) of data, more than 70 times the contents of the entire U.S. Library of Congress, on a single 5-inch disc. Yet the vast storage amount is limited by the ability to write data quickly enough to the device.

In the , researchers at Sun Yat-Sen University in China have demonstrated a way to record on ferromagnetic films using a laser-assisted ultrafast magnetization reversal dynamics.

The technique uses so-called time-resolved polar Kerr spectroscopy combined with an alternating magnetic field strong enough to re-initialize the magnetization state of gadolinium-iron-cobalt (GdFeCo) . Tianshu Lai and colleagues showed that the magnetization reversal could occur in a sub-nanosecond time scale, which implies that next- generation magneto-optical storage devices can not only realize higher recording densities but also ultrafast data writing of up to a gigahertz. Such speed is at least thirty times faster than that of present hard disks in computers.

Laser-assisted was demonstrated on a sub-picosecond time scale under a saturated external magnetic field. "We found that the rate of magnetization reversal is proportional to the external magnetic field," says Lai, "and the genuine thermo-magnetic recording should happen within several tens to hundreds of picoseconds when we apply a smaller than the coercivity of the recording films."

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Scientists post a lower speed limit for magnetic recording

More information: The article, "Field-dependent ultrafast dynamics and mechanism of magnetization reversal across ferrimagnetic compensation points in GdFeCo amorphous alloy films" by Tianshu Lai, Zhifeng Chen, Ruixin Gao, Zixin Wang, Chudong Xu and Daxin C. (Zhongshan (Sun Yat-Sen) University) appears in the Journal of Applied Physics.
Provided by American Institute of Physics
Citation: Progress toward terabit-rate high-density recording (2010, September 21) retrieved 19 October 2019 from
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User comments

Sep 21, 2010
I have a hard time filling my 1.5Tb HDD up with HD movie content, what the hell would someone do with 7Pb? virtual reality here we come...

Sep 21, 2010
It would be for servers. For home use, smaller is better with a RAID setup. Imagine filling a 6kTB drive, only to have it eventually crash.

Sep 21, 2010
This will help facilitate the eventual progression of personal data storage into the cloud, and nigh limitless storage space for everyone...

Sep 21, 2010
Oh, I remember the times when most of the content on the hard disk (other than the operating system and office programs), was created by the user.

Today, all the hard disks seem to be for storing stolen motion pictures. What a disgrace.

Sep 22, 2010
I would hardly call it a disgrace. The internet changed the game by making digital information so easy to copy and distribute. It was inevitable that our hdds would be full of video content - video files take up the most space!

Although if you are more upset about the "stolen" aspect of this, as opposed to the wasting of our hard drive space... well... too bad.

Sep 28, 2010

Although stealing is wrong and I rarely watch movies anyway, actors and actresses make too much money anyway. It's just like athelets. It's a joke that a circus clown makes more money than an engineer.

Oct 01, 2010
Yup. Looks like the meek shall not inherit the Earth. I wonder what else my parents lied to me...

Oct 03, 2010
Sour grapes aside I had a 1TB HD fail about 3 months ago and a 500GB fail 7 months before that. My 1TB HD was 3/4 full it had taken me nearly 6 months to fill it to that level. I am more interested in making the HDD more reliable than HD's having more capacity right now.

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