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Nanomagnets for Hard Drives
Single GNU Theory writes "Scientists at Cornell have developed magnets so tiny they could be used to create standard form-factor hard drives with terabyte capacities. All they need is a way to read and write them fast. Check it out here.
Hmmm... That'd require 250 Amiga Fast File System partitions! "
I just found this out from a friend who's studying electrotechnics here; the University of Twente, Netherlands, is developing a similar system.
:-)
with current technology all domain grains are irregular, and the stronger ones might start dominating the weaker ones over time, corrupting the data, so you need about 100 domains per bit, making one bit about 50nm in size. the solution to that problem is to make sure all domains are equal in strength. up to here it's the same as the nanomagnet theory.
the next problem is how to get those grains on a drive, and here is where it starts differing. the nanomagnet technology takes a number of nanomagnets and lines them up. the technology developed by the UT uses LIL, Laser Interference Lithography. the surplus magnetic material is etched away using two interfering laser beams, so in the first go you create lines of magnetic material. then you turn it by 90 degrees and repeat the procedure to create small islands of magnetic material, at perfectly equal distances. currently they're able to create a periodicity of 200nm, but with a new laser they could decrease that to 160nm, and with a new technique that is still in development they could decrease it even to 80nm. yes, 80nm per bit.
they've also designed a head with a one atom wide tip to read the data... the only real problem still is how to position that head accurately enough and quickly enough to allow for reliable, efficient and quick reading and writing.
so basically the University of Twente is already ahaid of Cornell University
)O(
the Gods have a sense of humor,
Never underestimate the power of stupidity
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this technology won't just enable you to create huge storage capacity in a standard size hard drive, but also teeny tiny hard drives with standard storage capacity... how big would a nano-magnet drive with 10GB capacity be? 0.5x1x2" maybe? imagine what that would do for portables and wearables. and a tiny drive like that would surely also take less power, yet another convenience...
)O(
the Gods have a sense of humor,
Never underestimate the power of stupidity
To err is human, to moo bovine
A terrabyte for portable MP3 players? Does anyone have that much music? Doing some quick math and assuming 1 minute = 1 meg (although you'd probably use something better if you had this capacity).
:-)
You'd be able to store 1048576 minutes of music, or 17476.26666667 hours, which is 728.1777777778 days or (assuming 365 days per year), 1.99500761035 years of music on a single disk.
I don't think that's the most pratical application of this technology
With this areal density, your wouldn't go for today's form factors. You could make a thumbnail-sized drive that would hold a few gigs, assuming that you could shrink the electronics, rotor, and servo down to similar scales.
One pressing question is whether today's rotary voice coil head actuators are accurate enough to position the head within +- 20 nm or so. Probably not.
If you check out the original site at Cornell you'll find this link where they talk about growing nerve cells on silicon. William Gibson's predictions coming true already....
--a proud Cornell class of 1970 alumnus
Thank God I'm an atheist!
Still reason to be optimistic, however.
They can't yet lay down a layer of these things into the track/sheets needed for a disk plater, for one thing. They had to do so individually, best I could tell, when what they want is to, perhaps, apply some sort of magneto-electric field, spray a mist of these magets embedded in a gel, and as the magnets settle towards the surface of the platter they'd align and space themsevles according to the field, and then as the gel/platter is heated the fields become erased and the surface solid and fixed for future use.
Then the problem of actually reading/writing to the disk.
The suggestion of a massively parallel fixed read arm would still have the problem of many 'wires' of the same size as the magnets, which might not be feasible.
If a motorized arm is used, we'd need something more precise and accurate than currently possible. Perhaps piezo-electric seek heads, grown within specifications, used to move the arm back and forth. As opposed to coils or something.
If I make no sense, please ignore, but I think those are some of the biggest hurdles to deal with.
AS
-AS
*Pikachu*
Presumably, if the heads are small there's less mass to crash into the magnetic surface (although less inertia to resist shock in the first place, of course) - which implies better shock resistance since the drive will get gouged less when you drop it.
Not that I'm in the habit of dropping my hard drives, of course, but it makes high-capacity MP3 players cheaper.
Dunx
Converting caffeine into code since 1982
Haven't used SFS (though I've heard a lot of good things about it); however, I do use PFS2 on my Amiga's hard drive and Zip disks. It's a similar idea to SFS; a file system that is organized in a less stupid way than FFS, and promises data coherency no matter what horrible things you do to your machine. It works perfectly; when the Amiga crashes in the middle of a write (which happens a lot to me, since there's no memory protection and I do a lot of silly things), it boots straight back up again. No corrupted filesystems, no waits while the filesystem is revalidated.
It's waaaaaaaay faster than FFS too, and has a hidden directory in the root of each filesystem which stores copies of the last thirty deleted files, so people who rm first and think later (like me) don't have to spend ages trawling through backups ;-)
I strongly recommend Amigans who still use FFS to check it out. UK Amigans can buy it from Ramjam Consultants.
How are we supposed to replace our magnetic media with something more esoteric when they keep making magnetic media more esoteric? Next I suppose they'll have little nanomachines pumping pedals to spin the drives...or they'll rotate the heads instead of the platters.
Yes it is possible with a cartesian grid. Put the grid on a magnetic drum, not a magnetic disk. Magnetic drums are particularly fast with head-per-track designs.
It might be zero time. The "teleportation of light" experiments in the past few years are altering a characteristic of light at a sensor. The researchers are considering using this for communication and computing. For communication, an entangled light beam could be sent between two places and alterations teleported between them...if entanglement works in zero time, bits could be sent across the country in zero time although the entangled light already made the trip at the speed of light.
Why have a rotary voice coil. One of the limiting factors in the drive is positioning the coil accurately. Just put an array of heads across the disk on a static arm -- one head for each track. You get an average seek time of only 1/2 rotation and no alignment issues. A lot of complex circuitry is eliminated, further shrinking the drive. Futhermore, you could get 1024 tracks read in parallel -- transfer rates would skyrocket.
I'm sorry I have to stop now, I'm drooling on my keyboard.
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