Fig. 3: Experimental observation of asymmetric topological pumping.
From: Asymmetric topological pumping in nonparaxial photonics
Three types of photonic-lattice configurations are considered, including engineering of height, period, and girder width profiles of the “H-shaped” structures in ultra-thin corrugated metallic coupled waveguide arrays. Schematic of altering a height, b period, and c girder width. d–f Near-field evolution of the measured electric field Ey at the excited frequency 11 GHz from the 1st site shows the openness of the pump channel. g–i Near-field evolution of the measured Ey from the 10th site show the disability of the pumping. Correspondingly, the two upper and lower panels in j, k, and l show the instantaneous field distributions at the propagation distances z = 0, 21, 42 cm, as shown by the black dotted lines in d–i, respectively, which are regarded as the chosen phase ϕ in one driven period equals to 0, π, and 2π, respectively.
