A sensing device comprising of a parabolic reflective surface and a bi-conical metal structure is proposed to focus terahertz energy on sample material in the sensing zone to create a strong interaction between terahertz signals and the sample under test. The signal enhancement by the sensing device is confirmed by modeling and simulation results. The proposed sensor is applied to investigate the polarization dependency of a split ring resonator (SRR), and spectral signatures of the SRR under different incident wave polarizations are obtained.
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