Figure 6: Robust transport at the edge of PTI.
From: Experimental realization of photonic topological insulator in a uniaxial metacrystal waveguide
(a,b) Close-up view of the sample with/without defect. (c,d) Transmission coefficients of the Ez/Hz field for the edge between PTI and POI. Black is for the case of no defect, while red is for the defect with five unit cells of star meta-atoms being substituted by gyro meta-atoms. The right-going spin-up edge state keeps moving rightward even when it encounters a defect, due to the absence of left-going spin-up edge state. (e,f) Measured transmissions for the edge between PTI and air waveguide. Robust transport can also be observed from 2.65 to 2.75 GHz where spin-filtered feature is maintained.
