Using Magnetic Bacteria to Manufacture a Better Hard Drive:
Hard drives are usually made by “sputtering”, in which clouds of argon ions are fired at a sheet of magnetic material, knocking off particles which are deposited as a thin film on a disc. Groups of these particles, called grains, form the magnetic regions on the drive, with around 100 grains corresponding to one bit.
Instead of granular media, Staniland’s team produce bit-patterned media. They start with a gold surface coated in chemicals in a chessboard pattern so that one set of squares binds proteins and the other repels them. They then apply the magnet-producing protein and coat the surface with an iron solution, which the protein-covered squares convert into magnetic material. As the name suggests, each magnetic square in bit-patterned media can store one bit. E
ach square Staniland’s team have so far produced is around 20 micrometres wide, far too bulky to store data with a density comparable to today’s hard drives. She says they now plan to test out nano-sized squares, 1000 times smaller and much closer to existing drive density. Eventually, she hopes to create a hard drive with a single iron particle per square, which will store as much as 1 terabyte of data per square inch - far beyond the capability of most hard drives.
(via Magnetic bacteria create a biological hard drive - tech - 09 May 2012 - New Scientist)