Terahertz-elasticity measurements on elastomers

The optical parameters (refractive index, absorption coefficient) of opaque dielectric materials can be measured with terahertz (THz) Time-Domain spectroscopy (TDS). By using a THz beam of known polarization and measuring both components of the transmitted THz field, it is possible to determine the birefringence present in an anisotropic material. In this work we used polarization sensitive (PS) TDS to determine the strain-induced birefringence in stretched elastomers.