GalliumArsenide
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IBM creates consistent electron spin inside semiconductors, takes spintronics one twirl closer
A fundamental challenge of developing spintronics, or computing where the rotation of electrons carries instructions and other data rather than the charge, has been getting the electrons to spin for long enough to shuttle data to its destination in the first place. IBM and ETH Zurich claim to be the first achieving that feat by getting the electrons to dance to the same tune. Basing a semiconductor material on gallium arsenide and bringing the temperature to an extremely low -387F, the research duo have created a persistent spin helix that keeps the spin going for the 1.1 nanoseconds it would take a normal 1GHz processor to run through its full cycle, or 30 times longer than before. As impressive as it can be to stretch atomic physics that far, just remember that the theory is some distance from practice: unless you're really keen on running a computer at temperatures just a few hops away from absolute zero, there's work to be done on producing transistors (let alone processors) that safely run in the climate of the family den. Assuming that's within the realm of possibility, though, we could eventually see computers that wring much more performance per watt out of one of the most basic elements of nature.
CCNY, UC Berkeley develop lasers that could rewrite quantum chips, spin those atoms right round
Computers are normally limited by the fixed nature of their chipsets: once the silicon is out of the factory, its capabilities are forever locked in. The City College of New York and University of California Berkeley have jointly developed a technique that could break chips free of these prisons and speed along quantum computing. They found that hitting gallium arsenide with a laser light pattern aligns the spins of the atoms under the rays, creating a spintronic circuit that can re-map at a moment's notice. The laser could be vital to quantum computers, which can depend heavily or exclusively on spintronics to work: a simple shine could get electrons storing a much wider range of numbers and consequently handling many more calculations at once. Research is only just now becoming public, however; even though gallium arsenide is common in modern technology, we'll need to be patient before we find quantum PCs at the local big-box retail chain. Despite this, we could still be looking at an early step in a shift from computers with many single-purpose components to the abstracted, all-powerful quantum machines we've held in our science fiction dreams.
Researchers use lasers to supercool semiconductor membranes, blow your mind
Ah, lasers. Those wonderful, super intense beams of light that we've seen used in headlights, projectors, and naturally, death rays. Like us, researchers at the Niels Bohr Institute at the University of Copenhagen figure there's nothing lasers can't do, and have figured out a way to use them to cool a bit of semiconducting material. This bit of black magic works using a membrane made of gallium arsenide and is based upon principles of quantum physics and optomechanics (the interaction between light and mechanical motion).Turns out, when a one millimeter square membrane of gallium arsenide is placed parallel to a mirror in a vacuum chamber and bombarded with a laser beam, an optical resonator is created between them that oscillates the membrane. As the distance between the gallium arsenide and the mirror changes, so do the membrane's oscillations. And, at a certain frequency, the membrane is cooled to minus 269 degrees Celsius -- despite the fact that the membrane itself is being heated by the laser. So, lasers can both heat things up and cool them down simultaneously, and if that confuses you as much as it does us, feel free to dig into the science behind this paradoxical bit of research at the source below. In other news, left is right, up is down, and Eli Manning is a beloved folk hero to all Bostonians.
Ultra-pure material lets electrons discover each other on the quantum dance floor
These guys aren't Purdue University professors, they're DJs. That thing on the left? It isn't a high-mobility gallium-arsenide molecular beam epitaxy system, it's their decks. It creates an ultra-pure material so perfectly latticed that it traps electrons between its layers and stops them bouncing around like drunken fools at the high school prom. By squeezing them ever so tightly, it lulls the particles into an "exotic" slow dance, at which point they become "aware" of each other and start performing correlated motions that are essential for quantum computing. That's a still a long way off, but if one day we find ourselves affixing gallium arsenide swabs to our quantum motherboards, we'll raise our lighters in the air. Informative PR after the break.
