COLUMBUS, Ohio -- In a development that holds potential for both data storage and biomedical imaging, Ohio State University researchers have used a new technique to obtain the highest-ever resolution MRI scan of the inside of a magnet.
Chris Hammel, Ohio Eminent Scholar in Experimental Physics, and his colleagues took a tiny magnetic disk -- measuring only 2 micrometers (millionths of a meter) across and 40 nanometers (billionths of a meter) thick and were able to obtain magnetic resonance images its interior.
The resulting image -- with each "pixel" one tenth the size of the disk itself -- is the highest-resolution image ever taken of the magnetic fields and interactions inside of a magnet.
Why look inside magnets? Because studying the material's behavior at these tiny scales is key to incorporating them into computer chips and other electronic devices.
The researchers report their findings in the August 12 issue of the journal Nature.
In 2008, Hammel's team debuted a new kind of high-resolution scanning system that combines three different kinds of technology: MRI, ferromagnetic resonance, and atomic force microscopy.
Ferromagnets -- the type of magnet used in this study -- are magnets made of ferrous metal such as iron. Common household refrigerator magnets are ferromagnets.
Because ferromagnets retain a particular polarization once magnetized, they are already essential components in today's computers and other electronics, where they provide data storage alongside computer chips. But smaller magnets built directly into a computer chip could do even more, Hammel explained.
"We know that shrinking these magnets to the nanoscale and building them directly inside electronics would enable these devices to do more, and with less power consumption," Hammel said. "But a key barrier has always been the difficulty of imaging and characterizing nanomagnets."
Typical MRI machine
|Contact: Chris Hammel|
Ohio State University