Looking Inside Magnetic Storage
Though solid state memory, like flash memory, is becoming more and more common in computer today, most everyone has worked on a computer with a classic magnetic hard disk drive. Inside of these are platters where each bit is written to a magnetic region, so the smaller the region, the more data can be stored. Companies have been looking for ways to shrink those regions, including making the platters multi-layered. Now researchers at NIST, the University of Maryland Nanocenter, and Royal Institute of Technology in Sweden have developed a method to find defects within these three dimensional magnetic structures.
This new technique looks to spin waves in a thin film. Spin waves are oscillating changes in the magnetic field of particles, like ripples in a pond. To achieve a ripple effect that spreads throughout a material requires the microwaves that are causing the spin waves to be at the resonant frequency. The researchers however used a different frequency, so spin waves would only be generate underneath their probe. By keeping the spin waves in the one area, the researchers are able to measure any defects which disrupt the waves.
By allowing researchers to better study defects in a magnetic material, researchers can figure out ways to either remove the defects, or work with them for more advanced storage methods.