Integrated CNT Aerogel Absorbers for Sub-THz Waveguide Systems

The ongoing development of sub-THz systems and applications has created a need for new absorbing materials which can be integrated in a simple, low-cost manner. Here, we investigate the properties of CNT-based aerogels in the range of 67–110 GHz and develop a simple technique for their integration. The aerogels are synthesised using standard techniques and then shaped using a laser cutter to allow for direct integration. The S-parameters of a total of four aerogel absorber samples are measured. The absorbers offer a return loss of up to 12–14.5 dB across the measurement band, with a maximum absorption of 5 dB/mm. The observed performance makes CNT aerogels extremely promising candidates for use in sub-THz waveguide systems and applications.