Two scientists have been awarded the 2007 Nobel Prize in physics in recognition of a discovery that helped hard drive makers cram even more data on to hard disks.

Albert Fert, of France, and Peter Grunberg, of Germany, will share the prize for simultaneously discovering GMR (giant magnetoresistance). Fert is a professor with Université Paris-Sud in Orsay. Grunberg is affiliated with the Research Centre Julich, in Julich, Germany.

According to the Nobel citation from the the Stockholm-based Royal Swedish Academy of Sciences, GMR is "a physical effect that "opened the door to a new field of science, magnetoelectronics (or spintronics), where two fundamental properties of the electron, namely its charge and its spin, are manipulated simultaneously".

Fert and Grunberg made their discovery in 1988, but within 10 years, the discovery was commercialised by vendors such as IBM, who developed ways of mass-producing hard drives that capitalised on this effect to store data much more densely than before.

GMR material has changed the storage industry, Dean said. IBM leveraged the technology by integrating GMR technology into hard drive designs, which doubled the capacity of its drives every year, Dean said.

"That fuelled the growth of storage of information and without it we would not be listening to music on an iPod," he said.

"Both Fert and Grunberg are deserving of recognition," Dean said. "They figured out how nature worked, saw this family of material called GMR and leveraged it to help society and make money too," Dean said.

The Nobel selection committee apparently agreed with Dean's assessment.

Portable music players with high-capacity storage are a fruit of this revolutionary phenomenon, the Nobel citation noted. "With a music player in the pocket of each and everyone, few still stop to think about how many CDs' worth of music its tiny hard disk can actually hold." the citation said.

The GMR effect replaced earlier technology of induction coils as read-out heads in hard drives. Induction coils are still used to write data on the disk. IBM is now looking to apply GMR technology to tape storage and MRAM (magnetoresistive random access memory), memory that stores data bits using magnetic charges.