Gizmodo: electrons

Breakthrough Spintronics Single-Electron Pump To Bring Faster, More Efficient Processors

Jesus Diaz — Fri, 16 Jan 2009 10:45:49 EST

Stay with me for a second here: Imagine a chip that can transport electrons while controlling the way they are rotating. OK, forget about this. I don't really know what I'm talking about. They do:

We study single-parameter quantized charge pumping via a semiconductor quantum dot in high magnetic fields. The quantum dot is defined between two top gates in an AlGaAs/GaAs heterostructure. Application of an oscillating voltage to one of the gates leads to pumped current plateaus in the gate characteristic, corresponding to controlled transfer of integer multiples of electrons per cycle. In a perpendicular-to-plane magnetic field the plateaus become more pronounced indicating an improved current quantization. Current quantization is sustained up to magnetic fields where full spin polarization of the device can be expected.

See what I mean? Here's the translation: By using the electrons spin, you can transport more information faster and using less energy than with normal chips, which just push electrons. The invention could lead to the development of "spintronics", which some people postulate as the future of information technology.

Hmm. OK, translation 2: Electron spins. Faster computers. Less power. Cool kickassery. [AIP via Nanowerk]

Scientists Build Worlds Smallest Transistor: Just One Atom Thick

Kit Eaton — Fri, 18 Apr 2008 06:52:06 EDT

Just the other day we were banging on about graphene, the new "wonder material" based on graphite, and now a British team has used it to craft the world's smallest transistor. It's just one atom deep and ten wide, and we don't need to tell you that that's teeny. In fact, it's more than three times smaller than the 32nm transistors at the cutting edge of silicon-based microelectronics: so it looks like Gordon Moore's law of transistor shrinkage has a bit of life in it yet.

Of course advances in semiconductor transistor fabrication will shrink the minimum size down from 32nm soon enough, but when 10nm is reached the cold, hard laws of physics will get in the way. And that's why the graphene transistor is important, since the research team at the University of Manchester says their transistor is already working at just 1nm.

It's made by taking a sheet of graphene, made using standard semiconductor fab techniques, and carving it with an electron beam. This creates a central quantum-dot with a voltage-sensitive conductivity, much as in conventional transistors. Amazing. The one flaw is that for now it's hard to produce graphene in large quantities: the biggest crystals made so far are less than 0.1mm across, and that's too small for mass production. The Manchester team thinks it won't be long until that problem is solved though. Will that mean graphene-chip supercomputer power in pocket sizes? We'll have to see. [Wired Science]

Silicon Out, Graphene In?

Sean Fallon — Mon, 24 Mar 2008 20:10:46 EDT

Physicists at the University of Maryland have demonstrated that graphene, a single-atom-thick sheet of graphite, has a greater ability to conduct electricity than any other known material at room temperature. In fact, electrons can travel up to 100 times faster in graphine than silicon, making it a likely candidate to replace it as a semiconductor material in devices like computer chips and sensors.

Graphene also has a resistivity (opposition to the flow of electric current) of 1.0 microOhm-cm—which is 35% less than copper. That figure would also make graphene the lowest resistivity material at room temperature. However, impurities in graphine make it less effective than copper at transferring electrons (at least for the moment). Still, with some refinement, the future looks promising for graphene as our next "miracle material." [University of Maryland via Slashdot]