For the first time, a team from the University of Minnesota Twin Cities has created a thin film of a special topological semimetal substance that has the potential to produce more computational power and memory storage while consuming considerably less energy. The ability to closely examine the substance allowed the researchers to draw some significant conclusions regarding the physics behind its special characteristics.
The study is published in Nature Communications, a peer-reviewed scientific journal that covers the natural sciences and engineering.
There is a rising need to increase semiconductor manufacturing and fund research that results in the development of the materials that power electronic gadgets worldwide, as demonstrated by the United States’ recent CHIPS and Science Act.
The majority of today’s computer chips are made using conventional semiconductors, but engineers and scientists are constantly exploring for novel materials that may provide more power while using less energy in order to improve, shrink, and optimize electronics.
A family of quantum materials known as topological semimetals is one such candidate for these new and enhanced computer chips. These materials possess special qualities that are not present in normal insulators and metals utilized in electrical devices due to the distinct behaviors of the electrons within them.
As a result, its potential for use in spintronic devices, a replacement for conventional semiconductor devices that rely on the electrical charge of electrons rather than their spin to store and process information, is being investigated.
In this new study, an interdisciplinary team of the University of Minnesota researchers was able to successfully synthesize such a material as a thin film and prove that it has the potential for high performance with low energy consumption.
One of the main contributions of this work from a physics point of view is that we were able to study some of this material’s most fundamental properties.Normally, when you apply a magnetic field, the longitudinal resistance of a material will increase, but in this particular topological material, we have predicted that it would decrease. We were able to corroborate our theory to the measured transport data and confirm that there is indeed a negative resistance.
Professor Tony Low
“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.”
Although topological materials have been studied for many years, the University of Minnesota team is the first to produce this semimetal in a thin film format using a proprietary, commercially viable sputtering method. 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.”
The fact that the researchers created such a superior material allowed them to closely examine its characteristics and understand what makes it so special.
“One of the main contributions of this work from a physics point of view 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 you apply a magnetic field, the longitudinal resistance of a material will increase, but in this particular topological material, we have predicted that it would decrease. We were able to corroborate our theory to the measured transport data and confirm that there is indeed a negative resistance.”
Low, Mkhoyan, and Wang have been working together for more than a decade on topological materials for next generation electronic devices and systems this research wouldn’t have been possible without combining their respective expertise in theory and computation, material growth and characterization, and device fabrication.
“It not only takes 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 transition of the technology from lab to industry,” Wang said.
In addition to Low, Mkhoyan, and Wang, the research team included University of Minnesota Department of Electrical and Computer Engineering researchers Delin Zhang, Wei Jiang, Onri Benally, Zach Cresswell, Yihong Fan, Yang Lv, and Przemyslaw Swatek; Department of Chemical Engineering and Materials Science researcher Hwanhui Yun; Department of Physics and Astronomy researcher Thomas Peterson; and University of Minnesota Characterization Facility researchers Guichuan Yu and Javier Barriocanal.
This research is supported by SMART, one of seven centers of nCORE, a Semiconductor Research Corporation program, sponsored by the National Institute of Standards and Technology (NIST). T.P. and D.Z. were partly supported by ASCENT, one of six centers of JUMP, a Semiconductor Research Corporation program that is sponsored by MARCO and DARPA. This work was partially supported by the University of Minnesota’s Materials Research Science and Engineering Center (MRSEC) program under award number DMR-2011401 (Seed).
Parts of this work were carried out in the Characterization Facility of the University of Minnesota Twin Cities, which receives partial support from the National Science Foundation through the MRSEC (Award NumberDMR-2011401). Portions of this work were conducted in the Minnesota Nano Center, which is supported by the NSF Nano Coordinated Infrastructure Network (NNCI) under Award Number ECCS-2025124.
