The founding fathers of modern hard drive technology have been awarded the Nobel Prize for Physics.

The Royal Swedish Academy of Sciences said that French-born Albert Fert and German-born Peter Grünberg both revolutionised the technology commonly found in music players and laptops today.

Fert and Grunberg independently discovered Giant Magnetoresistance (GMR) in 1988. Very weak magnetic changes give rise to major differences in electrical resistance in a GMR system.

A system of this kind is the perfect tool for reading data from hard disks when information registered magnetically has to be converted to electric current.

Researchers and engineers soon began work to enable the use of the GMR effect in read-out heads.

The first read-out head based on the GMR effect was launched in 1997 and this soon became the standard technology. Even the most recent read-out techniques are further developments of GMR.

A hard disk stores information, such as music, in the form of microscopically small areas magnetised in different directions. The information is retrieved by a read-out head that scans the disk and registers the magnetic changes.

The smaller and more compact the hard disk, the smaller and weaker the individual magnetic areas. More sensitive read-out heads are therefore required if information is packed more densely on a hard disk.

The GMR effect was discovered thanks to new techniques developed during the 1970s to produce very thin layers of different materials.

If GMR is to work, structures consisting of layers that are only a few atoms thick have to be produced. For this reason GMR is also considered one of the first real applications of nanotechnology.