Physicists Score Nobel Win for Nanotech Breakthrough

Albert Fert of France and Peter Grünberg of Germany are the joint winners of the award for their independent discoveries of Giant Magnetoresistance (GMR), an effect in which very weak magnetic changes give rise to major differences in electrical resistance.

GMR is considered one of the first real applications of the field of nanotechnology, according to the Royal Swedish Academy of Sciences, which granted the award. It has also made possible the compact hard disks used in today's laptops and music players.

Fert and Grünberg will split the prize of 10 million kronor (US$1.5 million) between them.

Revolutionary Technology

GMR technology has revolutionized the way data is read on hard disk drives, which store information such as music in the form of microscopically small areas magnetized in different directions.

Information from hard disks is retrieved by read-out heads that scan the disk and register the magnetic changes. The smaller and more compact the hard disk, the smaller and weaker the individual magnetic areas, making it necessary to find more sensitive read-out heads in order to allow information to be packed more densely.

By using the GMR effect in a read-out head, very small magnetic changes can be converted into significant differences in electrical resistance and therefore into changes in the current emitted by the read-out head, making ever-tinier drives possible. The first read-out head based on the GMR effect was launched in 1997, and the technology quickly became a standard. Today, even the most recent read-out techniques are further developments of GMR.

A Transforming Force

"They have basically enabled today's world of computing," Roger Kay, president of Endpoint Technologies, told TechNewsWorld. "I remember drives the size of car tires -- their work has transformed disk drive technology."

Indeed, it is because of Fert's and Grünberg's work that the industry is "converging rapidly on the terabyte disk drive," Kay added.

Such a drive requires 8 billion bits, or magnetic nodules, and they need to fit into a small space on the desktop, without generating too much heat or requiring too much electricity, he noted. "That's what these gentlemen have made possible," he said.

Precursor to GMR

The precursor to GMR, known as anisotropic MR, gave rise to a generation of hard disk technology commonly known as MR heads, John Rydning, research manager for hard disk drives and components for IDC, told TechNewsWorld.

Until the development of MR technology, the industry had been using a technique in which one structure, wrapped in copper wires, had to do both reading and writing on and off the disk, Rydning explained. That technology allowed the industry to increase capacities by about 25 percent per year through about 1990, he said.

Then, in 1991, the industry began using MR heads, the precursor to GMR, Rydning said. Capacities then were able to be increased by about 60 percent per year through the latter years of the decade.

"By that point, the industry was again looking at the possibility of the technology running out of steam," he explained. "They were finding it more and more difficult to continue to increase the amount of capacity on the disk."

Skyrocketing Capabilities

Following the introduction by Felt and Grünberg of GMR, capacities increased by about 100 percent per year for about five years, Rydning said. "It was a very dramatic change, and one of the shortest amounts of time I can think of between a technology being discovered in the lab and then commercialized in a product, especially with such a substantial impact on the industry."

To view that impact another way, the industry shipped about 42 million disk drives in 1992, which was the first year MR technology began to show up in hard drives, Rydning said. In 1999, after GMR appeared, the industry shipped 173 million drives. In 2004, following the five-year growth spurt enabled by GMR, the industry shipped over 300 million drives, he said.

"We talk a lot about Moore's Law," Rydning concluded, "but I would argue that the impact of the GMR effect on storage has been just as important an event for technology."