A View from David Zax
A Spintronics Breakthrough
Dispatches from the frontiers of quantum computing.
Researchers from IBM will be announcing a breakthrough in the field of spintronics this week, in the journal Nature, reports Computerworld’s Lucas Mearian. (A “huge” breakthrough, no less.) Spintronics is short for “spin transport electronics.”
Though it may sound like an outmoded style of breakdancing, spintronics could actually be the future of computing. The basic idea behind spintronics is to use an electron’s spin–up or down–to encode a one or a zero. The spin of the electrons can then be used to encode data.
This is all well and good in theory, but the problem is that electrons typically can only hold their spin for 100 picoseconds, or 100 trillionths of a second. A 1 GHz processor can’t possibly cycle that fast, so you couldn’t use the electrons’ spin for computing.
But what if you could extend how long electrons hold their spin? That’s exactly what IBM Research and the Solid State Physics Laboratory at ETH Zurich say they’ve done. They were able to stretch out electrons’ spin time by a factor of 30, to 1.1 nanoseconds. A 1 GHz processor can cycle in that amount of time.
“Usually, such spins find electrons randomly rotating and quickly losing their orientation. In this study, IBM and ETH researchers found, for the first time, how to arrange the spins neatly into a regular stripe-like pattern – the so-called persistent spin helix.”
This essentially proves a theory proposed back in 2003.
Why is spintronics exciting? It could eventually enable more precise control over the magnetic movements inside devices, especially as circuitry approaches atomic size. (At that point, to be able to read the spin of electrons rather than their charge–the current means of encoding and processing data–would be helpful.) It could also lead the way towards more energy-efficient gadgets.
That may not happen anytime too soon though–currently, the researchers have only been able to create their extended spin at -378 degrees Fahrenheit. I don’t know about you, but I wouldn’t want to pull out my iPhone in that kind of cold.
Spintronics is a field that’s been slowly but surely developing. Back in 2010, for instance, scientists at the University of Utah were able to show that it was possible to store information in spin and read it easily, reported NPR (drawing from this paper in Science). Go far enough down in the spintronics rabbit hole, and you start having to talk about multiple universes. As one researcher told NPR, “You can along those lines think about a quantum computer as many parallel computers running in different universes.” Or as Stephen Lyon of Princeton put it, “It’s not an easy one to explain… it’s kind of magical.”
Difficult to explain or not, if the researchers working in spintronics continue their advances and figure out a way to bring all this weirdness into the realm of room temperature, we could have a powerful new generation of computing devices on–and in–our hands.