"Magnetic Tornadoes" Could Offer New Data Storage Tech

coondoggie writes to tell us about the latest technique researchers are investigating as a possible means to store data, magnetic tornadoes. "Conventional computer memories store data in "bits" that consist of two magnetic elements that record data in binary form. When these elements are magnetized in the same direction, the computer reads the bit as a '0'; when magnetized in opposite directions, the bit represents a '1,' researchers stated. According to scientists, a vortex forms spontaneously — one vortex per disk — in a small magnetic disk when the disk's diameter falls below a certain limit. Although the vortex does not whirl about like a meteorological tornado, the atoms in the material do orient themselves so that their magnetic states, or 'moments,' point either clockwise or counterclockwise around the disk's surface. At the center of the disk, the density of this rotation causes the polarity of the vortex core to point either up out of the disk or down like a tornado's funnel, researchers stated. Because the vortices that form on the disks contain two independently controllable and accessible magnetic parameters, they could form the basis for quaternary bits that would contain data written as a 0, 1, 2, or 3."

Comments

There are 1 types of people who understand quints

[neo]

I suppose you'll get some kind of increase in data storage this way, but wont read/write times be longer because you'll need to deal with translations between quaternary and binary?

Re:There are 1 types of people who understand quin

[Yetihehe]

No, you can read it like two bits at once. Those bits would be actually separate channels for separate binary physical states, not one quaternary state.

Re:There are 1 types of people who understand quin

[thedonger]

Data storage increase is the first thought I had. But if solid state drives win the drive war, at least at the consumer level, it may be irrelevant. It's not like your WD Caviar will magically harness the power of quarternarian tornadoes and jump from 100GB to [something] TB. Or more. I think it may require more than just a firmware update.

Information Theory?

[Ristoril]

I read an article about Information Theory a long, long time ago (which is probably why I can't Google it) wherein the authors demonstrated that the most efficient means of storing information would be by using an alphabet that had e (2.71828183) letters.

It was pretty interesting and has been stuck in my head. In any event, they surmised further that the closest we could get would be if we came up with some sort of trinary alphabet. They also opined that we were damned lucky to have binary as it's the next-most-efficient alphabet.

Re:Information Theory?

[MarkPNeyer]

It's pretty easy to derive this result.

Suppose you have an alphabet with 'S' different Symbols. There are S^N possible strings of length N. The authors say of that paper claim that the difficulty in reading an N digit string is proportional to the product SN. Therefore, what we'd like to do is minimize the product SN while keeping S^N Constant.

That means we define k = S^N, and therefore ln k = N ln S, so N = (ln k / ln S). That means we're trying to choose an S to minimize f(S) = S * (ln k / ln S).

If f(S) = (S / ln S) * ln(k), then
f'(S) = (S*(-1/S) + + ln(-S))* ln k
f'(S) = (-1 + ln(-S)) * ln k

The function reaches its minimum when the derviative is 0, so:

0 = (-1 + ln(-S))* ln k
1 = ln(-S)
1 = 1/ln(S)
ln(S) = 1
S = e

Re-discovering magnetic bubble memory

[goombah99]

This sounds a lot like magnetic bubble memory that intel, fujitsu, IMB and TI made in the 1980s.

That too had multiple states per "bubble". However the higher-order bubbles were generally not used. The reason was, it was hard enough keeping the single bit (zeroth order mode) bubbles stable at high circulation and high density.

Since here the domains are fixed and the disk moves it might be easier to use higher order magnetic domain modes.

Gigaquads

[jack2000]

Well Star Trek already measured everything in quads... so yeah. Truth in television! Also Voyager was very fond of "Gigaquads".