Dielectric Properties of BaTiO₃–Epoxy Nanocomposites in the Microwave Regime

Abstract

We synthesized BaTiO3–epoxy nanocomposites (particle size k and low-loss nanocomposites. By comparing the theoretical predictions and the experimental data, four applicable effective-medium models are suggested. The retrieved dielectric constant (loss tangent) of 100-nm BaTiO3 nanopowder is in the range of 50–90 (0.1–0.15) at 8.2–12.5 GHz, exhibiting weak frequency dispersion. Two multilayer microwave devices—total reflection and antireflection coatings—are designed based on the fabricated nanocomposites. Both devices show good performance and allow broadband operation.

Keywords

• high-<i>k</i> epoxy nanocomposites
• microwave dielectric characterization
• effective medium theory
• Bragg reflector
• antireflection coating