For the first time ever, engineers from the University of California, Berkeley, have shown that magnetic chips can function at the lowest fundamental energy dissipation possible under the laws of thermodynamics, a breakthrough that could lead to a reduction in the power consumed by modern computers.
The new findings reveal a power consumption reduction that is as little as one-millionth the amount used per operation by transistors in modern computers. Power reduction is essential for mobile devices, which require powerful processors that can run for long periods of time on lightweight batteries.
"We wanted to know how small we could shrink the amount of energy needed for computing," said Jeffrey Bokor, senior author of the study. "The biggest challenge in designing computers and, in fact, all our electronics today is reducing their energy consumption."
Finding new ways to lower energy consumption is a new focus in recent years due to the shift in the industry from larger devices to smaller ones with an increased amount of transistors.
"Making transistors go faster was requiring too much energy," said Bokor. "The chips were getting so hot they'd just melt."
Back in 1961, IBM Research Lab's Rolf Landauer found that in any computer, each single bit operation has a minimum amount of energy that it must expend. Boker and his team, which included Jeongmin Hong, a postdoctoral researcher from UC Berkeley, set out to determine lowest amount of energy required for computer operation, an amount that hinges on the temperature of the computer, using a formula created by Landauer.
The team used a novel technique to measure the energy dissipation that takes place when they flipped a nanomagnetic bit by using a laser probe to trace the direction of the magnetic field as it was rotated from "up" to "down" position, or vice versa, using an external magnetic field.
The results revealed that just 15 millielectron volts of energy were required to flip the magnetic bit at room temperature, revealing the minimal amount of energy required for computer operation.
Although integrating such chips into modern computer production cycles will require more time and research, the findings show plenty of promise for the computer technology industry.
"The significance of this result is that today's computers are far from the fundamental limit and that future dramatic reductions in power consumption are possible," the author's wrote.
The findings were published in the March 11 issue of Science Advances.
