Nobel nanogiantism

Hard drive technology was valued at 10 million crowns

The Royal Swedish Academy of Sciences awarded the Nobel Prize in Physics to the Frenchman Albert Fert and the German Peter Grünberg. Their discovery of the giant magnetoresistance (GMR) effect is noted. This technology made it possible in the second half of the 90s of the last century to create a new type of computer hard drives. The GMR effect made it possible to pack information more compactly, which made a small revolution in technology. “Winchesters” have become much smaller in size, following which the electronic computing units themselves have become smaller. Firth and Grunberg turned out to be one of the fathers of modern portable computers - small laptops and very small handhelds.

French and German physicists will divide 10 million Swedish kronor in half. Nobel prizes are often divided into shares, which usually means that the discovery was made in two or three steps, and each of the laureates solved their part of the problem. So, for example, this year's prize in the field of physiology and medicine was divided . But in this case there was a classic conflict of priorities: Firth and Grunberg discovered giant magnetoresistance in their research centers independently and achieved results almost simultaneously. Their pioneering works in scientific journals appeared one after another - in 1988 and 1989. The Nobel Committee decided that they would not study the photo finish, and gave each of the physicists a gold medal.

Fert-Grunberg's discovery was based on a phenomenon long known to scientists: in the presence of a magnetic field, the resistance of a conductor changes. But usually these fluctuations are relatively small and the deviation is only a few percent. A Frenchman and a German managed to create a sandwich material that reacts to a magnetic field much more strongly. It consisted of alternating thin layers of iron and chromium. The first metal, as is known, is highly magnetizable (and many traditional information recording technologies are based on this), while chromium does not “remember” the direction of the magnetic field.

It turned out that if both layers of iron are magnetized equally, then the resistance of this “nanosandwich” is relatively small. But if you change the polarity of one of the layers, the resistance increases sharply - by tens of percent. Later, Albert Firth himself was able to explain this unexpected effect: according to modern theory, this is due to the fact that in such a thin conductor the spin (angular momentum) of the electrons begins to influence the characteristics of the electric current. But, perhaps, what is important is not why this effect occurs, but that less than ten years have passed from the moment of its discovery to practical implementation.

Already in 1997, the first hard drives based on the GMR effect appeared on the market. They differed from the previous ones by being more compact and having higher capacity. There is even a special direction in applied electronics called spintronics. When they talk about the now trendy nanotechnologies , among everything else that fits the appropriate size, they also mean devices that use gigantic magnetoresistance. So the research of Firth and Grunberg (the latter, by the way, quickly received a patent for his technology and over time cut off the coupons due to him from the discovery) turned out to be especially relevant in our century. What the Swedish academics who decided the fate of the Nobel millions could not ignore.

Albert Firth and Peter Grünberg worked independently of each other, but achieved the result almost simultaneously.

Vladimir DZAGUTO