Thin film of unique semimetal could boost power for electronics

A University of Minnesota Twin Cities team has synthesised a thin film of a unique topological semimetal material that could generate more computing power and memory storage while using less energy. The researchers also studied the material, leading to important findings about the physics behind its properties. The study was published in Nature Communications.

The United States’ recent CHIPS and Science Act has revealed a growing need to increase semiconductor manufacturing and support research that goes into developing the materials that power electronic devices. While traditional semiconductors are the technology behind most current computer chips, scientists and engineers are looking for new materials that can generate more power with less energy.

One candidate for these new computer chips is a class of quantum materials called topological semimetals. The electrons in these materials behave in different ways, giving the materials unique properties that typical insulators and metals used in electronic devices do not have. For this reason, they are being explored for their use in spintronic devices, an alternative to traditional semiconductor devices that leverage the spin of electrons rather than the electrical charge to store data and process information.

A team of researchers successfully synthesised such a material as a thin film — and proved that it has the potential for high performance with low energy consumption. Jian-Ping Wang, a senior author of the paper, said the research shows 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,” Wang said.

The University of Minnesota team is reportedly the first to have used a patented, industry-compatible sputtering process to create this semimetal in a thin film format. Because their process is industry compatible, the technology can be easily adopted and used for manufacturing real-world devices. Because the researchers fabricated such a high-quality material, they were also able to analyse its properties.

Tony Low, a senior author of the paper, said one of the main contributions of this work is that the researchers were able to study some of the 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.”

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