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A group of scientists led by Duke University has designed a new class of materials that can withstand incredibly high temperatures while producing tunable plasmonic properties.
Plasmonics is the technique of confining light energy within groups of electrons that oscillate together on a metal surface. This creates a strong electromagnetic field that interacts with incident light, allowing the device to absorb, emit, or control specific frequencies across much of the electromagnetic spectrum.
The new material is hard enough to stir molten steel and can withstand temperatures in excess of 7,000 degrees Fahrenheit. Coupled with their newly discovered plasmonic capabilities, carbides could improve communications and heat regulation in technologies such as satellites and hypersonic vehicles.
The study will be published online October 11 in the open access journal Nature Communications.
“The standard metals used in plasmonics research, such as gold, silver and copper, melt at relatively low temperatures and must be protected from the elements,” says Nanoscience at Consiglio Nazionale delle Riquerce in Modena, Italy. said Arrigo Calzolari, a researcher at the Institute. This means it cannot be used for rockets, satellites, or other aerospace applications. However, these new materials we are developing are capable of producing plasmonic effects at incredibly high temperatures, thus opening up a whole new realm of work. “
This ability stems from a class of disordered ceramics called “high-entropy” carbides, discovered in 2018 by Stefano Curtarolo, a professor of mechanical engineering and materials science at Duke University. These high-entropy carbides abandon the reliance on crystal structures and bonds that hold traditional materials together, relying on combinations of many disordered elements of varying sizes to increase stability. A pile of baseballs cannot stand by itself, but a pile of baseballs, shoes, bats, hats, and gloves may only support a resting baseball player.
“After running our recipe ideas through the chaos models and computations we’ve been developing, we found that they have plasmonic properties and that we can tune them by tweaking the recipe.”
Stefano Curtarolo
The original group of high-entropy materials is made of carbon and five different metallic elements, technically making them a class of carbides. Since then, Curtarolo has secured a $7.5 million grant through the U.S. Department of Defense’s Multidisciplinary University Research Initiative (MURI) competition that will allow him to design a series of similar materials with tailored properties as needed. Developed an AI material tool.
Calzolari knew about these materials and the project led by Curtarolo. He also knew that tantalum his carbide (a parent yet simple system) was very durable and exhibited plasmonic capabilities in the visible spectrum. However, this material cannot be tuned to different frequencies of light outside its natural range, which limits its usefulness in practical applications. ) may exhibit tunable plasmonic properties over a wide range.
In less than half a year, they were proven right.
“Arrigo came to me to confirm that these carbide mixtures work and have plasmonic properties,” said Curtarolo. “After running our recipe ideas through the chaos models and computations we’ve been developing, we found that they have plasmonic properties and that we can tune them by tweaking the recipe.”
In this paper, the researchers’ model shows that 14 different high-entropy recipes exhibit plasmonic properties across the near-infrared and visible spectrum of light, making them excellent candidates for optical and communications applications. They also worked with Douglas Wolfe, a professor of materials science and engineering and director of the Metals, Ceramics, and Coatings Processing Division at Penn State University’s Applied Laboratory to prove their theory experimentally. .
As a member of the MURI project led by Curtarolo, Wolfe was already familiar with high-entropy carbides. He happened to have his one sample of the recipe in question, so the group quickly demonstrated the plasmonic properties of his HfTa4C5, showing that they matched well with the computational model.
“These materials combine plasmonics, hardness, stability, and high temperature into a single material. you can’t.”
Stefano Curtarolo
This paper presents various configurations that perform or do not perform well with each other in various frequency ranges. The researchers plan to create new recipes and continue testing them for potential use in a variety of applications in antennas, light and heat manipulation, and any device exposed to extreme temperatures.
“These materials combine plasmonics, hardness, stability, and high temperature into one material,” says Curtarolo. “And they can be tailored to specific applications. This cannot be done using standard materials, as the properties defined by nature cannot be altered.”
This work is supported by the Office of Naval Research (N00014-21-1-2132, N00014-20-1-2525, N00014-20-1-2299).
Citation: “Plasmonic High Entropy Carbide”, Arrigo Calzolari, Corey Oses, Cormac Toher, Marco Esters, Xiomara Campilongo, Sergei P. Stepanoff, Douglas E. Wolfe, and Stefano Curtarolo. Nature Communications, 11 October 2022. DOI: 10.1038/s41467-022-33497-1
Online – https://www.nature.com/articles/s41467-022-33497-1
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