Hybrid organic-inorganic nanocomposites for terahertz applications
Résumé
The TeraHertz (THz) portion corresponds to the part of the electromagnetic spectrum having frequencies ranging from 0.3 to 10 THz. Unlike UV or X-rays, THz photons are not energetic enough to break chemical bonds or to ionize atoms or molecules. These radiations have found widespread applications in diverse disciplines for example in chemical sensing, identification of explosives, in security screening, and imaging of cancer. In spite of the tremendous progress in the development of THz sources, other components such as detectors, absorbers and modulators are required for effective control and manipulation of THz radiation. In the present study, we have examined the reflection and absorbance over a wide range of THz of hybrid organic-inorganic nanocomposites. By using free-space S-parameters THz measurements, such materials demonstrate a very low reflection and a high absorbance up to 99% in the range 0.2 to 0.5 THz. These properties are mainly due to the ability to associate mixed compositions at nanoscale and also the existence of a porous, sponge-like microstructure. Moreover, the absorbance level can be significantly varied by adjusting synthesis and processing parameters.