Cambridge (UK) - Christoforos Moutafis, a nanoscale researcher at Cambridge University, has uncovered some amazing magnetic properties of Iron-Platinum nanodots.  Something one of the scientists calls "non-trivial mathematical objects" have been discovered which reveal a type of magnetic monobubble.  It is a mathematical curiosity, but one which could form the foundational structure of future magnetic storage devices, like high-density hard drives or magnetic memory.


Scientists have had an age old desire to tap the world of the ultra-small.  Today's smallest production microprocessors we're all familiar with exist on 45nm process technology for fabrication which, while very small, is still many scores of atomic layers thick.  But imagine a storage device with the smallest components comprising only a few atoms, and one with the ability to change state very rapidly, 1000s of times faster than today's hard drives.  That's just one potential of the monobubble nanodot.

The monobubble nanodots being studied today are tiny groups of FePt (Iron Platinum) atoms.  They exhibited some interesting magnetic properties which led one researcher named Christoforos Moutafis to say, "These are cylindrical domains of magnetization anti-parallel to its surroundings and perpendicular to the nanodot.  We have called this bi-domain state the 'monobubble' state."  What he's saying can be explained by the next image.  The concentric rings of blue, purple and yellow represent magnetic sections within the nanodot.  The color changes and directional lines indicate pole changes from its outter-most state, to the middle neutral state, and then to the opposite state on the inmost position.

The monobubble consists of a tri-state magnetic field, blue, purple and yellow as shown above. The monobubble exhibits interesting magnetic properties which are still being researched.

Moutafis explained that the magnetic states responded in a particular way when probed.  This is analgous to the giant magnetoresistance phenomina, or GMR, which is what makes high-density hard drives possible.  Two scientists were recently awarded the Nobel Prize for Physics for the GMR discovered in 1987.  In this nanodot device, for example, when a field or current was applied the probe received significant changes in observable data based on the monobubble's various states.  This is the monobubble equivalent of GMR.

Research is a long way from actual product, however.  And research is continuing.  These kinds of scientific endeavors may eventually yield no application fruit.  However, it provides insights into the world of the uber-small where we're still finding out that effects like GMR are possible.  Who would've thought 20 years ago we'd have 500 GB hard drives for less than $100 which fit in a single socket?  This nanodot technology has potential to give us the same in another 20 years.  "Dad, you mean you used to have to store your HD movies on separate discs?  Wow!"

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