New Scientist, 14:54 07 September 04, Will Knight
Journal reference: Nanoscience and Nanotechnology (doi:10.1166/jnn.2004.107)
Nanoscopic dots of nickel that could be used to store terabytes of data in a computer chip just a few centimetres wide have been created by US researchers.
Each “nanodot” consists of a discrete ball of several hundred nickel atoms and can have one of two magnetic states. This allows them hold a single bit of information, as a “1” or a “0”.
In a conventional computer hard drive, information is stored on a disk coated with a magnetic material, and bits must be far enough apart not to interfere with each other. Nanodots should allow bits to be packed closer together as the dots are discrete units that are not structurally linked. …
The researchers used a pulsed laser to heat nickel until it turned into plasma – an amorphous form of matter with positively and negatively charged atoms. In this form, the nickel rearranged itself on two different substrates – aluminium oxide and tin titanium nitrate – as uniform dots.
The dots arranged themselves at a density that would, theoretically, allow about five terabytes of data – five thousand gigabytes – to be packed into computer drive roughly the size of postage stamp. …
The fabrication technique could perhaps be used in other ways. It was also possible to arrange the dots in three dimensions within a substrate. The pair found the nanodots could be arranged in a uniform manner within the crystalline structure of tin titanium nitrate. In theory, this could strengthen the crystal lattice of a molecule, perhaps leading to the development of novel, super-strong materials, Narayan says.