3D Dirac Plasmon Quasiparticles

Plasmons—quantized collective oscillations of electrons found in conventional metals and semiconductors—are attracting interest for applications in sensing, fast electronics, and solar cell technology. Plasmons can also exist in exotic solids known as Dirac materials. Dirac plasmons present many advantages over conventional ones, such as a higher propagation velocity and frequency tunability. Dirac plasmons have so far been observed in 2D materials like graphene. However, 2D plasmons are extremely sensitive to the presence of defects and contaminants on the material’s surface. Now, Antonio Politano, from the Italian Institute of Technology–Graphene Labs in Genoa, and colleagues have provided direct evidence of 3D Dirac plasmons in the bulk of platinum ditelluride (PtTe2).