Fig. 1
a Schematic of the Rice–Mele waveguide lattice. b Instantaneous eigenvalue spectrum for a waveguide array designed to exhibit the Rice–Mele model, Eqs. (2)–(4), over the full adiabatic pump cycle. c Spectral decomposition of the wavefunction over the instantaneous eigenstates of the ordered system with periodic boundary conditions, |φn〉, as a function of the propagation distance. The simulated supercell contains 30 unit cells. The instantaneous eigenstates are ordered by their energy, so all of the upper band (i.e., occupied) states of the system are shown on the right half of this plot. d Histogram of the experimentally observed displacements of the waveguide array as light is injected into the bulk of the system one waveguide at a time. Different colors represent different incident wavelengths, λ = [1450, 1500, 1550, 1600, 1650 nm], listed in order of cyan to magenta. e Three exemplars of the direct observation of transport at the output facet of the waveguide array at λ = 1650 nm. The waveguide locations are outlined in green circles, except for the location of the initially excited waveguide, which is outlined in yellow
