The smaller they come...
Small is certainly beautiful. And what better way to attest to this than this year’s Nobel Prize for Physics that salutes developments in nanotechnology. Albert Fert of France and Peter Grunberg of Germany share the honour for discovering Giant Magnetoresistance, or GMR — a physical effect based on nanotechnology that is revolutionising digital data storage. As with most discoveries, GMR’s potential was realised only in the late 1990s, more than a decade after Fert and Grunberg stumbled on to it while trying to find out how to squeeze more and more data into increasingly smaller spaces. Ever since, it has been driving a virtual explosion of information technology as physicists use it to develop highly sensitive tools for reading information stored on hard disks.
Not surprisingly, the immediate application of GMR was in the electronics industry that came up with smaller disks to store data — an incredible drive of miniaturisation of hard drives in electronic gadgets like iPods and laptops that continues. Scientists always knew that it is possible to cram more information on to hard disks by shrinking the size of the magnetic areas where individual bits of data are stored in the form of 1s and 0s. The problem, though, was that smaller areas produced weaker shifts in magnetism, making the resulting changes in electrical resistance too feeble to be detected by conventional technology. Fert and Gruenberg solved this by alternating ultra-thin layers of magnetic and non-magnetic material to produce GMR, which boosts the weak electrical signals. GMR exploits a quantum characteristic of electrons called ‘spin’ that prompts them to act like miniature magnets pointing up or down. If scientists some day manipulate this ‘spin’, we can expect more breakthroughs that will generate new industries, just as the understanding of how electrons can be moved in a conductor by applying a potential difference led to electric lighting, the telephone, computing, and many other industries that we take for granted.
India cannot afford to miss the nanotechnology bus and should make investments in it carefully. The country has inarguably one of the largest talent pools in the world. But, unfortunately, research seems to be exclusively focused on nano-materials, while little of note is being done in nano-electronics.