About | News & Features | Science Highlights

A Different Spin

JANUARY 28, 2016

In the mid-1960s, Silicon Valley pioneer Gordon Moore made a now-famous prediction that the number of transistors incorporated in a chip would approximately double every twenty-four months. This maxim—known as Moore’s Law—has been the impetus for semiconductor development ever since.

A Different Spin
  • David Mandrus removes a crucible from a glowing hot furnace. High temperatures and controlled atmospheres are needed to produce new crystalline materials. Photo by Jennie Andrews.

For nearly five decades Moore’s Law rang true, but the days of exponential progress may be in jeopardy. Improvements in chip performance are approaching a roadblock due to the properties of the materials involved.

David Mandrus is a leading researcher in the field of quantum materials who creates and studies new substances with unique properties relating to magnetism and conductivity. He says new materials like those being conceived in his lab could clear the hurdles facing current technology.

“Silicon technology has been very important in the advancement of devices, but we are getting to a point where their constraints are limiting new breakthroughs,” Mandrus explained. “By designing new materials and tuning their properties, we can come up with the kind of improvements people seek.”

That’s exactly why the Gordon and Betty Moore Foundation recently selected Mandrus to receive a $1.7 million grant to further his research. As the Jerry and Kay Henry Endowed Professor in UT’s Department of Materials Science and Engineering, Mandrus is an expert in the emerging field of spintronic materials.

Processors in today’s electronic devices use electric fields to regulate electrons via their charge. But electrons also have a spin that makes them act like tiny magnets. By manipulating these magnets using magnetic fields, Mandrus hopes to create new spintronic materials that take advantage of both the charge and spin of electrons.

“The idea is to control electrons using magnetic fields as well as electric fields,” Mandrus said. “This will lead to new device concepts and a new generation of electronic devices that require very little power to operate.”

Greater efficiencies are achieved when the spin of electrons becomes more uniform. Spintronics creates the equivalent of an interstate highway for data to travel on—unlike current materials, which are more like a meandering country road.

“Manipulating the spin of electrons can increase the amount of data flowing through a material while reducing the power needed to operate the device,” Mandrus said.

The tricky part is building and testing at a nanoscopic level. Mandrus and his team are developing single-layer materials—just a few atoms thick—that can be stacked on top of each other in any number of combinations. “Think of it like building a sandwich,” he explained. “There are limitless ways of putting one together, each with its own unique result.”

Finding the best sandwich for the job also requires analyzing various layer alignment options. Mandrus hopes to eventually build a “library” of single-layer materials and how they interact with one another. Such a compilation could open the door to creating chips in a revolutionary way.

“It’s a fresh approach to easing the limitations related to modern devices,” Mandrus said. “By changing the way information is stored or utilized, you change the performance as well.”

A drop in the power requirement would obviously be great for portable electronic gadgets, and it just might make the tantalizing concept of the “Internet of Things” a reality. Imagine multiple devices—not just phones and TVs but also washing machines, thermostats, and toasters—all connected to each other.

It could potentially lead to other developments like “smart” cars with sensors to avoid crashes, making them safer and more efficient than current technology allows.

As society continues to adapt to an all-electronic world, it could, ironically, do so by consuming less power.

Original Source: UTK Quest

By: David Goddard