News | Materials
Researchers at Liten, a CEA Tech institute, have discovered what makes the vibrational spectrum of manganese silicides so unique. Their research was published in the journal Nature Communications.
Manganese-silicide-based crystalline materials—whose low thermal conductivity is crucial for applications in thermoelectricity, spintronics, and optoelectronics—were recently the topic of some in-depth research by Liten scientists.
The team used ab initio calculation methods to model the vibrational spectrum of the heat carriers in the materials, revealing behaviors far more complex than those observed in semiconductor materials like silicon. For starters, the manganese silicides' vibration modes include diffusion. The researchers also discovered very-low-frequency optical vibration modes. These modes are caused by the unique twisting movements of the materials' silicon substructures and are responsible for the materials' thermal anisotropy. The researchers' theoretical calculations were corroborated by neutron-diffusion experiments conducted on large instruments in the United States.
The results have not yet been formally correlated to manganese silicides' thermoelectric properties; however, they do provide scientists with valuable insights that will aid in identifying new materials of interest.
CEA is a French government-funded technological research organisation in four main areas: low-carbon energies, defense and security, information technologies and health technologies. A prominent player in the European Research Area, it is involved in setting up collaborative projects with many partners around the world.