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Spin doctors put quantum effects into data storage on the smallest scale?

Expect more misleading and just plain wrong articles about the "spintronics" breakthrough than anything you've read all year. The basic story is that America's Naval Research laboratory has "generated, modulated, and electrically detected" a pure spin current in silicon.

Spin, one of the quantum characteristics of an electron, is not spin in the disk sense. It's not even spin in the political sense. Nothing in ordinary electronics can prepare the general public for the concept of spin current.

The excitement is due to the fact that the breakthrough holds the possibility of taking data storage down to the tiniest level - down to the level of the electron. How long it can take before this theoretical demonstration can be translated into a technology isn't mentioned once in the Eureka Alert report, and the abstract simply repeats the assertion that storage may be one application... one day.

But the main problem is in the word "spin" itself. In one sense, it refers to rotation. But in quantum physics, it's a misleading word. Electrons themselves have "spin" - but do not rotate.

As the Wikipedia article says: "Spin is particularly important for systems at atomic length scales, such as individual atoms, protons, or electrons. Such particles and the spin of quantum mechanical systems ("particle spin") possesses several non-classical features and for such systems spin angular momentum cannot be associated with rotation but instead refers only to the presence of angular momentum."

So anything we read in the next few days about "very small disks made of individual electrons spinning" can be quietly ignored; and the prospect of using quantum disks to store your MP3s can be ignored for at least another five (probably ten) years.