Modified elastomeric polymers for loss reduction in the terahertz range

A method of reducing the dielectric loss of poly-dimethylsiloxane (PDMS) in the terahertz range with dopants is presented. Samples of PDMS are doped with varied concentrations of polytetrafluoroethylene (PTFE) micro-particles, and characterized with terahertz time domain spectroscopy (THz-TDS) in order to extract their material properties. It is found that controlled doping can significantly reduce dielectric loss in PDMS at terahertz frequencies, and for the sample with highest dopant concentration, a 15.3% average reduction in loss tangent is demonstrated over a range from 0.3 to 1 THz. Measured material properties are compared with the Lichtenecker logarithmic mixture formula, and approximate agreement is attained.