Bilayer Polymer Metacomposites Containing Negative Permittivity Layer for New High-k Materials.

Polymer matrix high-k composites are of considerable interest in various electronic devices, such as capacitors, antennas, actuators, etc. However, how to enhance the permittivity without elevating the loss remains a challenge for us. Here we present a novel design of bilayer high-k metacomposites consisting of two stacked single layers with positive permittivity and negative permittivity. Interestingly, the bilayer system shows an obvious permittivity boost effect with a permittivity improved by a 40-fold increase compared with the polymer matrix, while maintaining a loss tangent as low as 0.06. Further calculation results indicate that the permittivity of the bilayer composites could be enhanced by 4000-fold or even a greater increase as compared with the polymer matrix via balancing the dielectric properties of single layers. Insights into how the thickness ratios and dielectric properties of single layers interfere with the dielectric performances of bilayer composites were discussed. This study provides a new route for the design of high-k materials, and it will have great significance on the development of dielectric materials. Hopefully, multilayer high-k metacomposites with fascinating dielectric performances could be achieved via balancing the dielectric properties of single layers.