This year’s Nobel Prize for Physics, it was announced today, has been awarded to Albert Fert, from Orsay, Paris, and Peter Grünberg, from the Jülich research centre in Germany, for their discovery of giant magnetoresistance, an effect whereby a structure of layers of alternating magnetic and non-magnetic materials, each only a few atoms thick, has an electrical resistance that is very strongly changed by the presence of a magnetic field.
The discovery was made in 1988, and at first seemed an interesting but obscure piece of solid state physics. But very soon it was realised that this effect would make it possible to make very sensitive magnetic read heads for hard disks. On a hard disk drive, information is stored as tiny patterns of magnetisation. The higher the density of information one is trying to store on a hard drive, the weaker the resulting magnetic field, and so the more sensitive the read head needs to be. The new technology was launched onto the market in 1997, and it is this technology that has made possible the ultra-high density disk drives that are used in MP3 players and digital video recorders, as well as in laptops.
The rapidity with which this discovery was commercialised is remarkable. One probably can’t rely on this happening very often, but this is a salutory reminder that sometimes discoveries can move from the laboratory to a truly industry-disrupting product very quickly indeed, if the right application can be found, and if the underlying technology (in this case the nanotechnology required for making highly uniform films only a few atoms thick) is in place.