We investigate the effects of disorder on metamaterial samples composed of split ring resonators with randomly introduced variation in their geometrical dimensions. We demonstrate that disorder broadens the negative permeability band and introduces effective losses into the system. Transmission measurements on samples with varying degrees of disorder are found to be in excellent agreement with predictions based on standard homogenization theories.

Nd : YAG laser triggering of a centimetric air gap in a homogeneous electric field is studied for pressures ranged from 0.5 to 5 bar. Breakdown transient voltage and current are measured and the formative time lag dependence on reduced field and laser intensity is analysed. It is quantitatively shown that the laser field strongly influences the time lag to breakdown through the effective reduced field.