|Photomontage of a diamond and a hard-drive head. (Courtesy: I Jakobi)|
A nitrogen-vacancy (NV) defect in diamond has been used to create a magnetometer that can measure the broadband magnetic fields generated by hard-disk write heads. The work was done by researchers in Germany and the UK who have shown that a single NV can detect the oscillating and static magnetic fields associated with write heads at nanometre resolution. The new work could help further miniaturize hard-disk drives, thereby increasing their data-storage capacity.
"The hard-disk industry currently has no established sensors that can resolve the magnetic field of write heads on the scale of 5–10 nm," explains team-member Ingmar Jakobi of the University of Stuttgart. "This is a serious impediment for developing these devices, which will carry the biggest share of data in the ever-growing digital world."
The NV defect in diamond offers a solution to this problem because it comprises a single electron spin that is highly isolated from its immediate surroundings. This spin is essentially a tiny magnet that could be used to detect changes in a magnetic field over nanometre distances.
Diamond magnetometer could help shrink computer hard drives, Belle Dumé