  We characterize the behaviour of split ring resonators made up of
high-transition temperature YBCO superconductor using terahertz time domain
spectroscopy. The superconductor metamaterial shows sharp change in the
transmission spectrum at the fundamental inductive-capacitive resonance and the
dipole resonance as the temperature dips below the transition temperature. Our
results reveal that the high performance of such a metamaterial is limited by
material imperfections and defects such as cracks, voids and secondary phases
which play dominant role in partially impeding the flow of current causing
dissipation of energy and electrical resistance to appear in the superconductor
film.
