For many years, efforts have been made to reduce energy consumption in computers and electronics. One way to accomplish this is through the creation and application of new materials with distinct properties.
For the first time, a team from the University of Minnesota Twin Cities created a thin film of a novel topological semimetal material that has the potential to generate more computing power and memory storage while using significantly less energy. The researchers were also able to closely examine the material, which resulted in some significant discoveries about the physics underlying its unique properties.
The research was published in Nature Communications, a peer-reviewed scientific journal devoted to natural sciences and engineering. As evidenced by the recent CHIPS and Science Act in the United States, there is an increasing need to increase semiconductor manufacturing and support research that goes into developing the materials that power electronic devices worldwide. While traditional semiconductors are the technology that powers the majority of today’s computer chips, scientists and engineers are constantly on the lookout for new materials that can generate more power with less energy, allowing electronics to be better, smaller, and more efficient.
This research shows for the first time that you can transition from a weak topological insulator to a topological semimetal using a magnetic doping strategy. We’re looking for ways to extend the lifetimes for our electrical devices and at the same time lower the energy consumption, and we’re trying to do that in non-traditional, out-of-the-box ways.Jian-Ping Wang
One such candidate for these new and improved computer chips is a class of quantum materials known as topological semimetals. The electrons in these materials behave differently, giving the materials properties that typical insulators and metals used in electronic devices do not have. As a result, they are being investigated for use in spintronic devices, an alternative to traditional semiconductor devices that use electron spin rather than electrical charge to store and process information.
In this new study, an interdisciplinary team of University of Minnesota researchers were able to successfully synthesize such a material as a thin film – and demonstrate that it has the potential for high performance with low energy consumption.
“This research shows for the first time that you can transition from a weak topological insulator to a topological semimetal using a magnetic doping strategy,” said Jian-Ping Wang, a senior author of the paper and a Distinguished McKnight University Professor and Robert F. Hartmann Chair in the University of Minnesota Department of Electrical and Computer Engineering. “We’re looking for ways to extend the lifetimes for our electrical devices and at the same time lower the energy consumption, and we’re trying to do that in non-traditional, out-of-the-box ways.”
Researchers have been working on topological materials for years, but the University of Minnesota team is the first to use a patented, industry-compatible sputtering process to create this semimetal in a thin film format. Because their process is industry-compatible, Wang said, the technology can be more easily adopted and used for manufacturing real-world devices.
“Every day in our lives, we use electronic devices, from our cell phones to dishwashers to microwaves. They all use chips. Everything consumes energy,” said Andre Mkhoyan, a senior author of the paper and Ray D. and Mary T. Johnson Chair and Professor in the University of Minnesota Department of Chemical Engineering and Materials Science. “The question is, how do we minimize that energy consumption? This research is a step in that direction. We are coming up with a new class of materials with similar or often better performance, but using much less energy.”
Because the researchers fabricated such a high-quality material, they were also able to closely analyze its properties and what makes it so unique.
“From a physics standpoint, one of the main contributions of this work is that we were able to study some of this material’s most fundamental properties,” said Tony Low, a senior author of the paper and the Paul Palmberg Associate Professor in the University of Minnesota Department of Electrical and Computer Engineering. “Normally, when a magnetic field is applied to a material, the longitudinal resistance increases, but in this particular topological material, we predicted that it would decrease. We were able to confirm the existence of a negative resistance by correlating our theory to measured transport data.”
Low, Mkhoyan, and Wang have been collaborating on topological materials for next-generation electronic devices and systems for over a decade; this research would not have been possible without their combined expertise in theory and computation, material growth and characterization, and device fabrication.
“It takes not only an inspiring vision but also great patience across the four disciplines and a dedicated group of team members to work on such an important but challenging topic, which will potentially enable the technology to transition from lab to industry,” Wang said.