Plasmonic systems have received considerable attention because they can be profitably used in a variety of applications that encompass telecommunications, antennas, molecular sensing and heat engineering. However, the standard metals used in plasmonics research, such as gold, silver and copper, melt at relatively low temperatures and need protection from the elements. That means they can’t be used in rockets, satellites or other aerospace applications, that require superior thermal and mechanical properties to work in harsh environments.

In 2018 a group of scientists led by Stefano Curtarolo, professor of mechanical engineering and materials science at Duke University, have engineered a new class of materials, known as high-entropy carbides, that exhibit attractive characteristics like extraordinary thermal stability, hardness, strength, toughness, as well as wear and oxidation resistance. These high-entropy carbides rely on a combination of many disorderly elements of various sizes to enhance stability.

Now Arrigo Calzolari from Cnr Nano, Stefano Curtarolo, and coworkers propose that some high-entropy carbides couple exceptional mechanical and optical prosperities, exhibiting a plasmonic activity in the near-infrared/visible range, whose characteristics can be tuned by controlling the chemical composition and the stoichiometry. New dedicated experiments performed by the group of Prof. Douglas Wolfe at Pennsylvania State University confirmed this discovery. The researchers report the materials in a paper in Nature Communications.

“These new materials we are developing open a completely new working arena because they can create plasmonic effects at incredibly high temperatures”, says Calzolari. “Overall, the discovery of plasmonic activity in high entropy carbides awakens the exploration of new structure-property correlations in this complex class of systems, opening up exciting avenues for future research”.

Further reading:

Read the Behind-the-Paper story featured in Nature Portfolio Materials Community: Plasmonic high-entropy carbides – Behind the paper