Washington, July 18 : Physicists at Ohio State University say that they have invented a new kind of MRI technique that may one day enable the development of extremely small computers, thus giving doctors a new tool for studying the plaques in blood vessels that play a role in heart disease.
In a recent issue of Physical Review Letters, they have reported the first-ever magnetic resonance image of the inside of an extremely tiny magnet.
"The magnets we study are basically the same as a refrigerator magnet, only much smaller," said project leader Chris Hammel, Ohio Eminent Scholar in Experimental Physics at Ohio State University.
The researchers have revealed that the disk-shapes magnets they involved in their study measured only two micrometers (millionths of a meter) across.
"Because ferromagnets generate such strong magnetic fields, we can't study them with typical MRI. A related technique, ferromagnetic resonance, or FMR, would work, but it's not sensitive enough to study individual magnets that are this small," they say.
They even say that the new kind of magnetic resonance may enable medical researchers to image plaques formed in the body, and thus eventually become a tool for biomedical research.
The technique combines three different kinds of technology-MRI, FMR, and atomic force microscopy-and has been dubbed the technique "scanned probe ferromagnetic resonance force microscopy" or scanned probe FMRFM.
It involves detecting a magnetic signal using a tiny silicon bar with an even tinier magnetic probe on its tip.
Hammel and his colleagues are beginning to record the properties of many different kinds of tiny magnets, a critical first step toward developing them for computer memory.
They believe that tiny magnets may someday be implanted on a computer's central processing unit (CPU) chip.
According to them, since system data could be recorded on the magnets, such a computer would never need to boot up. It would also be so small that the entire computer would be contained in the CPU.
Hammel and his colleagues also hope to contribute to the development of an instrument that will help researchers study in detail plaques that are associated with diseases like Alzheimer's and atherosclerosis.
The researchers, however, say that their technique needs some further development before it could become an everyday tool for the computer industry or for biomedicine.