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Thouless pump (1983): adiabatic cyclic evolution of a 1D lattice pumps exactly C quanta of charge per cycle, where C is the Chern number of the occupied band. The Rice-Mele Hamiltonian has hopping t±δt·cos(φ) and on-site potential ±Δ·sin(φ). As φ: 0→2π, the Wannier center (charge center) moves by exactly one lattice constant. This is the 1D analogue of the quantum Hall effect — topologically protected and immune to disorder.