Low‐loss percolative epsilon‐negative composites derived from the ultra‐low percolation threshold

Abstract

AbstractIn this work, the mechanism of negative permittivity response with low losses in the silver nanowires/polyvinylidene fluoride composites were demonstrated. Due to the large aspect ratios of silver nanowires, ultra‐low percolation threshold () between 0.7 and 0.8 wt% was achieved with the losses effectively decreased by several orders of magnitude down to a low level of about 0.2. The negative permittivity response from Lorentz type and Drude type presented the transition from insulator to conductor. The tunable Drude type negative permittivity was ascribed to the plasma oscillation of free electrons, which leads to an inductive property. The conduction mechanism was switched from hopping to metallic conduction with the observation of skin effect. The epsilon‐negative materials with lower losses have potential applications in communication devices, such as novel capacitors and antennas.