Experimental data for "Observation of a Topological Phase Transition in Random Coaxial Cable Structures with Chiral Symmetry"

Experimental study of coaxial cable structures which map onto disordered SSH (Su–Schrieffer–Heeger) chains.Data consists of spectra corresponding to the S-parameters, S₁₁ and S₂₁, (reflectance and transmission) for cable structures, consisting of 16 lengths of 50 ohm or 93 ohm coaxial cables. The structures map onto SSH chains: the transmission time for each cable is the same and chosen to make the zero energy in the mapping correspond to a frequency ~114 MHz.The data sets are for:Reflectance data for unlooped chains. In the figures in the paper, these are converted to impedance values. The spectra show the presence of a topologically protected state at zero energy.Reflectance data for looped chains. Converted to impedance values, this shows the presence of a degenerate pair of zero energy states in topologically marginal chains.Transmission data for unlooped chains. The spectra show the presence of extended states with high transmission in topologically marginal chains.<br><br>