March 26, 2014
First Steps Taken In Creating Diamond Transistors
Lee Rannals for redOrbit.com - Your Universe Online
Researchers from Ohio State University have demonstrated for the first time that information can flow through a diamond wire.
Scientists are working to develop “spintronics” in order to make computers simultaneously faster and more powerful. Spin could be used to help transmit data in computer circuits, and the latest research shows just how viable of an option diamonds could be.
The team wrote in the journal Nature Nanotechnology that they found electrons did not flow through the diamond as they do in traditional electronics. They discovered that electronics stayed in place and passed along a magnetic effect spin to each other down the wire.
“To a scientist, diamonds are kind of boring, unless you're getting engaged," lead investigator Chris Hammel, Ohio Eminent Scholar in Experimental Physics at Ohio State, said in a statement. "But it's interesting to think about how diamond would work in a computer."
The cost for the diamond wire didn’t reach engagement ring proportions, however. At a cost of only $100, the researchers opted for synthetic, rather than natural, diamonds.
The team’s finding represents the first step along a road that could eventually lead to diamond transistors. The discovery also could change the way researchers study spin, according to Hammel.
During the study, the team placed a diamond wire in a magnetic resonance force microscope and detected that the spin states inside the wire varied according to a pattern.
"If this wire were part of a computer, it would transfer information. There's no question that you'd be able to tell at the far end of the wire what the spin state of the original particle was at the beginning," he said.
In order to get the diamond to carry spin, the team had to seed the wire with nitrogen atoms for there to be unpaired electrons that could spin. The wire contained just one nitrogen atom for every three million diamond atoms, but that was enough to enable the wire to carry spin.
The researchers set the magnetic coil in the microscope to switch on and off over tiny fractions of a second, which generated pulses that created 15-nanometer wide snapshots of electron behavior. They knew the spin was flowing through the diamond when the magnet moved minute amounts as it was alternatively attracted or repelled by atoms in the wire.
The team also found that the spin states lasted twice as long near the end of the wire than in the middle. They suspect this effect was due to how closely they were able to zoom in on the wire. Hammel said their discovery challenges the way researchers have studied spin.
"The fact that spins can move like this means that the conventional way that the world measures spin dynamics on the macroscopic level has to be reconsidered—it's actually not valid," he added.