TRL Assisted Low-loss Negative-Refractive-Index Metamaterial Characterization in the Presence of Surface Effects

The characterization of metamaterials requires simulating or measuring samples with finite thickness. However, finite sized samples result in surface artefacts which cause an inconsistent wave-impedance to be retrieved when applying the Nicolson-Ross-Weir (NRW) method to low loss metamaterials. A method is demonstrated that uses thru-line (TL) deembedding to isolate the surface artefact allowing the NRW method to obtain consistent values of wave-impedance.